Certain inventions are acknowledged as the peak of human innovation and excellence. Fire, democracy, the automobile, and now, with the addition of the SCARPA Alien 4.0, that list has grown. Coming off the legendary 3.0 platform, the Alien 4.0 has made minor improvements for those who like to go uphill fast while having a stiff and precise boot on their feet. With an updated free-floating BOA® dial taken from similar boots in their lineup (Alien 1.1, F1 LT, e.g.), one can expect slightly better fine-tuning adjustments with a quick rotation of a dial. SCARPA has also updated the 4.0 by permanently adding foam on the upper cuff for better comfort and less fiddling out of the box. Because speed can mean safety in the mountain (as well as a podium finish), SCARPA has stuck with the Speed Lock Lite ski walk lever for single motion transitions along with Spectra cord that is easy to adjust while offering a stiff ride. SCARPA has stuck with Vibram UFO rubber under your feet which equates to solid traction on a mixed bag of terrain and excellent durability. The rockered sole gives it a trail-running feel. For fast and light days where weight, skiability, and range of motion are essential - the SCARPA Alien 4.0 is now the “Ferrari” of full-carbon ski boots.
- Full-carbon construction for the lightest boot option that SCARPA can offer.
- Updated free-floating BOA allows for better fine-tuning and heel retention.
- SCARPA Race 4.0 bikini liner offers a full-range ankle articulation as well as excellent thermo-moldability.
- Vibram UFO 4.0 outsole for maximum grip and durability on varied terrain.
- 76 degrees range of motion allows for the most efficient stride possible.
- Speed Lock Lite System means a fast and secure single motion transition.
- Dynafit Quick-step instep inserts are fast and reliable.
- Made in Italy so you know it must be good.
||BOA lower / Spectra cord with single throw for upper|
||9°-13° / 11°-15°|
||Race 4.0 SL|
||Vibram® UFO 4.0|
|Skimo Co Says|
|Usage||Racing, training, speedy touring|
|Notes||Padding added to the cuff to lessen the fiddle factor. No metal insert in heel for extra weight savings|
|Bottom Line||Winning races 4.0|
|Compare to other Race Boots|
Questions & Reviews
I just cracked my Alien3.0 (and my ancle) in an avalanche a week ago. Terrifying.
Are the spare parts, a whole carbon cuff available for the Alien3.0..?
My 281mm feet have more than enough space in the Alien3.0’s, do you think I would fit the new Alien4.0 in size 42?
Prepairing for NEXT season.
Oh no! Sorry to hear about your injury! While Scarpa does send us a lot of parts, boot cuffs are not among them; you might be able to secure a replacement if you reach out to Scarpa directly. The Alien 4.0 should use the same scafo (lower shell) mold as the 3.0's so I would expect the 4.0 to feel very similar to what you're used to.
seems that the new alien 4.0 comes without metal insert on the heel for the tech binding, as shown on the pics? ture??
i am looking for a skimo race boot.
My feet lengh is something around 266mm long and the forefoot width is 103mm.
How is the fit of this scarpa alien 4.0? Is this model narrow or width in the fit?
And how is the fit in the forefoot compared to the Pierre G. /Dynafit DNA or the la sportiva stratos? And are there any alternatives too these three ultra light racing boots?
Thanks a lot!
The Pierre Gignoux boots are a tad wider. The Stratos V says it has a wide 103 last, if you can find one.
Please email us for more. firstname.lastname@example.org
So the scarpa alien 4.0 would be to narrow for me, and the PG or the La sportiva would work? And sry that I ask, but what do you mean with a "2 finger passform" ? And do you mean a insole with a footbed?
My Alien 3.0 sz 42 is a bit more roomy for width and much more generous in the instep.
My sz 26 RC1-generation PG has a more noticeable forefoot width flair but still fits well, especially around the instep, although part of that is b/c it's really too short for me (and fits only via shaving down all the liner toebox foam, and even then it's just barely long enough).
The 44 will roughly work for 10.5 to Maybe 11.5. And these fit towards the narrow.
Please fill out our boot finder and I will see what we can find for you. Also, include an accurate foot length to us.
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