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SCARPA Alien RS Boot

$869.95 $629.95

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Every so often a company will debut a category-shattering display of engineering that seems to break all kinds of rules, defy stereotypes, and spearhead a new generation of skiing. Behold: the Alien RS. Holding true to the da Vinci mantra that "simplicity is the ultimate sophistication," the Alien RS is a delightfully simple boot. A stiff carbon-infused Grilamid cuff is mated to a stiff carbon-infused Grilamid lower by way of an unbelievably dexterous pivot that again, defies stereotypes. A Boa closure on the lower shell wraps around your foot to create a secure and precise fit. Racers, say hello to your new everyday boot light enough to sneak in 40,000ft of dawn patrols per week; freeriders, mountaineers, and steep skiers, say hello to your beefy race boot capable of taking you further than ever before.

  • Carbon Grilamid LFT Shell and Cuff blend industry-leading power-to-weight ratio with industry-leading price.
  • Lower Shell is built around a 3D Lambda Torsion Frame to increase lateral stability and power transfer.
  • Speed Cam Lock ski/walk mechanism is reliable, durable, and precise.
  • A waterproof, zippered gaiter tempts snow to even try to get into this boot.
  • Offset toe lugs promote a more natural walking motion to increase touring efficiency.
convert to ounces
920g [27]
983g [28]
Weight (pair) 1840g [27]
1966g [28]
Buckles 1 + BOA, Single Throw Speed Cam Lock
Boot Sole Length 270mm [24]
278mm [25]
286mm [26]
294mm [27]
302mm [28]
310mm [29]
318mm [30]
Binding Compatibility Tech Only
Cuff Rotation 72°
Forward Lean(s) 7°, 9°, 11°, 13°
Specs Verified Yes
Materials Carbon Grilamid LFT
Liner Intuition Cross Fit Tour
Sole Vibram UFO RS
Skimo Co Says
Usage Speed touring, high performance ski mountaineering, exceeding expectations
Notes Grilamid infused with long strands of carbon fiber increase torsional stability and precision. A zippered, waterproof gaiter invites you to use your imagination when accessing lines.
Bottom Line If the Holy Grail was a ski boot.
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Questions & Reviews

Trevor J (used product regularly)
Really an impressive boot. feels more like a shoe than any boot I had had. Great performance on almost all snow. On Rock hard crud it begins to show its limitations. Fits perfectly into my "quiver" of boots as the lighter of two. Thanks for the great boot.
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Jeff mikaelian (downright abused product)
I didn't really need to wait so long to review. Have been using for over a year, I knew they were the boot for me before I bought and have lived up to it every day. I am lucky that I fit Scarpa length perfectly and have a narrow with no issues foot.
Performance - They are plenty stiff, yes they don't have a very progressive flex but I quickly got used to them and isn't a thought anymore. Skiing powder is not a problem for my daily 100mm ski. And to the chagrin of Scarpa, I can drive my bigger powder ski.
Walk mode- no need to discuss, they are awesome. Hiking is so much less a chore. The ski/walk mode is excellent as is, hate to see it go. I can easily flip open and close with my ski pole. No bending over and messing with buckles and powerstraps. The cord slipping doesn't seem to be an issue for me and I do have it knotted. If you are one who really cranks buckles and power straps, you may not like, but for me, no problem
Durability-zero problems to date. I believe if properly fitted, and I have custom footbeds, you do not need to tighten the BOA much. For the majority of people, the BOA hasn't been an issue. Same with the cord, I don't overtighten and I don't even have any fraying yet. There does seem to be some wear points between the shell and liner. I have been trying to use the patches on the shell and tape to keep ahead of it.
From powder to suncupped summer snow I couldn't expect more from these. And seriously thinking of getting another pair before they become the LT
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Question from Shane K
Do you guys know if the BSL of the new F1 LT will be more like the Alien RS or F1? I see that's it's not a huge difference anyways and could just adjust my bindings. Just curious. Thanks!
Answer from Cole P
Hello Shane, the lowers on the F1 LT are almost identical to the Alien RS, and believe they will be similar if not exact to its BSL.
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Marcos (used product a few times)
Finally bought the boots!!! Just use them for a couple of days before returning home. On the uphill they have wings!!! Didn't have the oportunity to try them in a descent powder day yet, but so far happy on the downhill.
Had to tie a knot on the dyneema cord, the stopping mechanism kept losing tension.
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Question from Marcos
Hi, do this boots work with marker kingpin bindings?
Answer from TSB
Hey Marcos, unfortunately they do not, the overhanging shell plastic above the heel lip interferes with the alpine-style heel on the Kingpin. For a lighter boot that fits nicely with Kingpins, check out the La Sportiva Skorpius.
Answer from Marcos
What about the La Sportiva Sytron or the Dynafit PDG 2? The LS Skorpius are over my kilogram per boot limit...
Answer from TSB
Hey Marcos, you are unfortunately out of luck if you are looking to pair a sub-1kg boot with an almost-1kg binding. The Skorpius is your best bet for weight-to-compatibility ratio (it's even compatible with the mythical Ski Trab TR2 binding).
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Question from Albert
The comments thread indicates that the Alien RS will be discontinued after this season. Can you shed any light on this? I’ve been using the Maestrale RS/ Alien RS as the boot quiver and find it to be a fantastic combo. Hope that the Alien RS sticks around!
Answer from TSB
Albert, c'est vrai, the death of the Alien (RS) is imminent! Upon its discontinuation we plan to send a ceremonial pair out upon the Great Salt Lake in a boat assembled from Scarpa boot boxes, Grilamid-infused cannoli shells, and empty bottles of grappa. Stay tuned for Scarpa's next iteration in the "race-plus" category, though, which we hear will be an exciting blend of tradition and innovation, racing and touring, passion and temperance (and, supposedly, will have the same lower fit as the Alien RS).
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Lane A (used product regularly)
I got these boots thinking I would use them for long tours in the Cascades paired with Voile Objectives. They are certainly light and go uphill very well, but I think I had unrealistic expectations for the downhill performance. I'm sure they are good for the weight (I haven't skied other boots in this weight class), but don't expect them to be much fun in difficult snow conditions. If you ski nice light snow with a conservative style then they will do great. I usually opt for a heavier boot and bring these out for climbing focused objectives where skiing is more of an efficient way to get down than the main goal. Great boot for what it is, but don't expect a miracle. They make a lot of sacrifices to get a boot this light.

A few notes:
- Cord closure requires a stopper knot to prevent slipping which makes it difficult to dial in the tension or adjust throughout the day. The knot wears down one section and will probably break the cord eventually, but it looks easy to replace.
- Fit is much narrower than other Scarpa boots. All other Scarpa boots I have tried are way too wide for me but these fit well.
- Booster strap can be installed by drilling a hole in the back of the cuff. This helps the downhill performance a bit. I haven't broken the cuff yet, fingers crossed.
Reply from TSB
Hey Lane, thanks for your review! We haven't seen an epidemic of broken cords due to wear, so I wouldn't be too concerned (though it never hurts to pack an extra for those monthlong American Alps traverses). On the other hand, the power-strap mod is fully endorsed by ski tourers north and south (though it voids the warranty, of course).
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LCC Skier (downright abused product)
The Alien RS represents a huge step forward in the world of ski touring equipment. They are very lightweight, have excellent cuff articulation, and they ski very well. Full stop. Although they do take some getting used to, once you are familiar with the way these boots ski I do not see why you couldn't drive a fairly large ski at decent speeds. I highly recommend tuning the forward lean to suit your skiing style and going with as aggressive of a fit as is comfortable (you need a medium to narrow foot with high volume).

I will attempt to address few of the concerns many people seem to have about this boot. First, “it isn’t going to be warm enough on cold winter days”. In my experience, this boot is adequately warm for most very cold days (single digits F) especially when you are moving fast, and this boot should inspire you to do so. Second, “this boot isn’t going to be durable or reliable”. This boot is like many other ultra-light pieces of gear, I wouldn’t advise wailing on it. I did break my right cuff about an inch above the pivot while skiing one day, luckily Scarpa replaced the cuff for me in a (somewhat) timely fashion.

The Alien RS will become an absolute cult classic of a ski boot. Much like the TLT-6. Its performance greatly outweighs its mass, and I think that is the idea with most of the gear on this site. Get yourself a pair before they are gone. -Scarpa is canning the Alien RS for next season… :(

(Full disclosure: I did not but these boots from skimo.co but I really like this site and I think this is a great place to post and read reviews.)
Comment on this review:

Question from Nick B
Do you think this boot would be able to reasonably drive something like the hyper V8? That seems like a big ski, but I just realized it's a pretty similar weight to the standard v6, which does seem like something more in the wheelhouse of this boot.
Answer from TSB
Hey Nick, thanks for reaching out! The Hyper V8 is definitely designed for a slightly beefier boot than the Alien RS, but if you're mostly aiming to spoon low-angle powder turns, it's not a totally outlandish combination. The Alien RS is impressively stiff in the lateral direction so you'll be more than capable of getting onto your edges and turning the ski from a balanced stance -- more hip wiggle and less knee drive, if you will. You may want to mount a little forward of boot center to compensate for the more upright stance of the Alien RS, and of course be aware that you void the warranty of the boot by skiing it on anything over 85cm at the waist.
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Greg (used product a few times)
Just got a pair of these in a 30. Have put 2 days in then and am very disappointed in how sloppy they fit. I probably should have sized down, but then I’d have to punch the toe to make them long enough (2 separate bootfitters agreed). I have a pretty low volume foot and these things just have tons of heel lift, side to side, and up to down play in them. I’m literally swimming even with the Boa maxes. I’m going to try high volume footbeds and foam padding but short of that I’m afraid this boot just won’t work for me.
Reply from jbo
Hi Greg, sorry these boots aren't working for you. We don't recommend them for very low-volume feet. Next time you're in the market, please consider visiting our boot fitter and purchasing from us!
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Colby (downright abused product)
When it's working this boot is working right, doing what it is designed to do, it does it really well. It is stiff and can ski big, heavy skis fairly well. It's light and has great articulation. The lever/tightening mechanism works well and I have not had a problem with the cord.

However, it's also not super reliable in the field. I have broken the boa system a couple times, and while this isn't a deal breaker, it can be annoying to ski and hike with a loose lower, and it is a big pain to put a new cable in. The bolt that goes through the lever is a bit too short and the nylon on the lock nut doesn't quite engage the threads. I've lost the bolt while touring and almost lost it a couple other times when I realized the nut was going. Skiing out without being able to lock the upper boot can be quite grim. Finally, I've had the gaiter start separating near the cuff after only one season. I'm not sure how I'm going to fix that.

As others have mentioned: these boots are narrow and punching them would void the warranty. They are also a bit small and I would size up.
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Nat (downright abused product)
Hands down the best skiing boot I have ever used in this weight category. I use them with Voile Objectives and Helio 95's and they drive both skis very well. So light! And so easy to use. I think they're total game changers. Over the past 2 seasons I have put approximately 80 days on my Alien RS's and they are holding up surprisingly well. I have yet to have anything break or really fail. I do carry replacement / backup Dyneema cord but am still going strong on the originals. I also keep an eye on the walk/ski mode bolt and put some blue loctite on it for piece of mind. I expect to get another season or two out of them for sure!
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Question from Keith K
Hi, I wanted to know if this boot is compatible with Salomon/Atomic Shift bindings?
Answer from Jeff
Hey Keith!! No they would not. The toe is not a full DIN toe to work with a Shift binding. Pretty much only the 'Beef' boots at the bottom of our page of boots will work.
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Question from Beat Bischof
Is there a woman version of the Scarpa Alien RS Boot?
Answer from Jeff
Hi Beat! No, this is a unisex boot. They have a narrow last and a bit taller cuff. So if you have a low/large calf, maybe not a good fit.
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Question from Dave E
I skimmed through and saw lots of comparisons to other boots, but not to Alien 1.0. . . maybe I missed it.

So questions:

1. Does this boot ski as stiff as 1.0? If not as stiff, is that in a good way (like smoother flex closer to TLT6 vs the stiff brick wall of the 1.0?) or is it just flimsy like the original plastic alien?

2. The 1.0 has a fixed cord that you adjust by re-tying the knot and this boot looks like it has a cam to adjust more easily. When I have climbed vert ice with my 1.0, it seemed to work really well unbuckled but I wonder if the on-the-fly cuff adjustability of this boot would be a benefit climbing ice to get a little more cuff support and decrease calf fatigue?

3. Since this boot seems to have a more conventional liner, do people feel like it walks as well as the 1.0 or does the liner inhibit range of motion somewhat?

4. Lots of comments about durability. . any comment from Scarpa about changes or improvements next season?
Answer from Jeff
Dave, lets go through point by point:
1. Scarpa rates them 95 RS and 100 for the 1.0. But they are very different boots, the 1.0 is a Race boot with a stiff carbon cuff. The RS has been much refined from the original Alien to a race light touring boot. Forward flex is not flimsy and is considered by many to have the best downhill performance for a boot this light.
2. The cam is a nice touch, but still recommend tying a knot.
3. Range of motion is still excellent in the RS. New liner does not seem to restrict.
4. No announced changes next year, just adding a size 31.
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Question from Josh C
Hi Skimo folks,

The lean lock/locking lever screw keeps falling out. I lost one touring and one simply on the approach (hiking with the boots on my pack). I know this is a well documented problem but didn't see a solution mentioned after a quick scan through all the comments. I've about had it--and Scarpa customer service hasn't helped out by sending new screws despite several emails to them. I imagine you guys have a good work-around? Do you just recommend a screw from the hardware store with a locking nut? Any better suggestions? I almost thought I'd just put a ten-penny nail through it and bend it over but there has to be a better-engineered solution. Thanks.
Answer from Teddy Young
Hey Josh, I’m sorry that Scarpa hasn’t been getting back to you! Thankfully, a standard stainless steel bolt and locking nut from the hardware store are a sufficient fix here.
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Jim (downright abused product)
After a year of using these boots on a variety of trips from multi-day tours to quick uphill training skins at resorts, I have some observations. Overall, this boot is a good option for race training and lightweight shorter trips if you have a narrow-ish foot, and it skis extremely well for how light it is, but I can't recommend it as a daily driver or for longer tours in rugged terrain. It's simply not reliable enough. These are the failures I've experienced so far:

- Boa cable broke. Replaced with a free kit from Boa under warranty, but doing that job is a major PITA. Not something that could likely be done out in the field.

- Ski/Walk lever attachment screw fell out while on a tour. I cobbled together a fix with bits from my repair kit to get home, and then replaced the bolt with the closest approximation from a hardware store once home, but Scarpa used a weird diameter bolt for this, and the replacement is slightly more narrow which leaves a fair amount of slop in the lever pivot.

- Cuff cord broke clean through on a long tour yesterday, rendering the ski/walk mechanism and cuff closure useless. I made an emergency fix with a Voile strap to hold the cuff closed and permit me to ski downhill (sloppily), but now I have to figure out how to replace that darn cord. This also revealed another weakness in the ski/walk lever's design: there is nothing that actually locks the lever into ski mode; there's just a groove in the lever that a metal tab on the boot heel slots into. The two are held together solely by friction from the pivot/attachment bolt. But, if the ski/walk lever is worn around the bolt where it pivots, or that bolt had to be replaced with a slightly sloppier fitting one as in my case, the lever has little friction to hold it in place and can simply fall out of lock mode, which it did about 100 times to me yesterday.

A few notes about fit:

- It is a narrow and low-volume last, unlike other Scarpa boots such as the Maestrale, which is great for me since my feet are shaped liked toothpicks, but people who have normal feet might need some modifications to fit comfortably.

- Sizing runs small. I'm a 27.5 in alpine boots, 28.5 in all other touring boots, and a 29.5 in the Alien RS, which is borderline too small. If I keep these I will get a punch in the toe box to make more room.

- As others have noted, the toe box is oddly shaped and aggressively rounded off. This causes even narrow feet like mine to feel jammed into the sides of the toe box.

- Forward lean is minimal and forces a more upright stance.

If it was more reliable it would be a great option for me, but for now I'm shopping for something that won't break as often, even if it ends up being heavier.
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Adam Pohl (downright abused product)
The finest lightweight touring boot of all time. I have probably 200 days and 700,000+ vert on mine and they're still holding strong! I've skied tlt5s, 6s, backlands, f1s and several others, and really nothing comes close to the worry-free efficiency of the RS. The one caveat is that you really have to know how to ski for them to work. With a solid technical foundation and an understanding of the limitations of 1 kilo boots, they will take you anywhere. I ski them on 80mm mountaineering skis, all the way up to 110mm powder skis, and they've never complained once. They're the warmest, most comfortable boot i've ever had and when they die (they're close), i'll get another pair.
Comment on this review:

Silas Miller (used product a few times)

I had the pleasure of using this boot for three days before the cuff broke right above the ankle pivot on the outside of the left boot. The boots were amazing, but broke just from flexing forward skiing normal conditions. I attempted to warranty them and Scarpa denied the claim saying I “Overflexed” the boot. Total BS. I continued to baby them in SkiMo races and just found out the other boot broke in the same place. Such BS.

I don’t understand how people can ride these things and not break them. I’m only 150lbs and I broke both boots just by skiing groomers. (Probably because I’m so freakin fast!). Super pissed at Scarpa for not warrantying them. Can’t say I would recommend them to people.
Reply from jbo
Hi Silas, I would take these back to your dealer and have them process a warranty for you. It should be no problem, at least here in the U.S.. For what it's worth, we haven't seen any crack like this.
Reply from Elliott B
Just a note. This happened to me last year and Scarpa warrantied it no problem. They turned the boot around quick as well. I don't know why your experience was different. I thought that they were great actually.
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Question from Smith Stanton
Hey my Boa cable just broke as I was on the uphill. I’ve had maybe 10-12 outings on them. I’ve loved them till now. Aargh. Has this been an issue? Fixable, I am hoping? (Alien RS)
Answer from Brendan A
Just had the same thing happen! Also hoping I can repair this myself...
Answer from Kevin-Druis M

I have this boot for almost two seasons. Both my Boa cables broke at the end of last season. The first one i got replaced for free by Scarpa, and the second I did myself with a replacement kit... fairly easy. The wire they put in the stock RS is surrounded by a black plastic, and probably a bit thinner... so it is fragile compared to the typical Boa cable (So they told me at the Boulder Scarpa Repair Facility). By replacing it with a Boa cable without the outer plastic, the Boa tends to break less. I haven't had any problems this season, and I think Scarpa hasn't had people complaining about the new wires they replace the stock one with.

I will add that a Boa mechanism is relatively complex compared to other tightening options out there, hence you can expect something more fragile. But it is easy to replace with a simple kit, and the comfort of the adjustable tightness is amazing. In my opinion, this boot is worth it.

Hope that helps.
Answer from SMS
FYI: If you want to replace the Alien's RS original black plastic-coated cable then it is the "EX735 single lace" from Boa. But as Kevin stated above, Scarpa is now using the regular braided wire which is not coated. (Model #?) This is what they told me below:

"We have updated the boa to a metal cable instead of the plastic coated as it is much more durable. The repair we do requires a rivet press, as we replace all of the clips as well. I can send you the parts, but the better fix is to send it in to us. On a rush repair we can have it done in a few days once we receive it."

I am not sure why Scarpa feels the need to replace the clips. Maybe the clips have a tighter radius of curvature and would kink less?....just guessing. I'll see how the repair holds and maybe send boots in at the end of the season for clip replacement, if it still seems appropriate.
Answer from Brendan A
I recently tried to replace the boa myself, however have run into issues remounting the plastic bottom half of the boa back onto the boot - section that connects the boa cabling system to the outer boa dial. It seems that no matter what orientation I seem to use, it wont click back into place. Has anyone else run into the same issue?
Answer from SMS
Yes, I think I know what you are talking about. That little plastic tongue seems too stiff to snap into place. I filed a tiny bit of plastic away and then applied chapstick to the plastic and then placed it tongue first and then pushed the superior piece down and it did snap into place finally. Awkward for sure.
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Model: Alien RS

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