Grivel Duetto Helmet

Just got it, used it on a spring ski at Lassen in late spring storm. Great fit!!! 7 1/2 hat size, M/L fit great, wore it ALL day long, Mtn Bike to the upper parking with it, climbed with it and of course use it down hill...didn't know it was there until I remember to take it off in the parking lot. More comfortable them my trustie truckers hat.......

I tried on this helmet in the store and it was both the lightest and most comfortable helmet I have ever worn. I have a hard time finding helmets that fit, I am usually between a M and L with a wide forehead that often gets pinched in many lids. The Grivel Duetto felt like it was made for me, the only ski/climb helmet I have put on that felt right. Unfortunately I didn't have the self esteem that day to commit to the.. uh.. lets say "unusual" appearance of the helmet and I ended up getting the Petzl Meteor, which is the second best helmet I've used (and I've tried many) but every time I put it on I regret not getting the Duetto. At some point I will be back to buy it and commit to putting function over form.

How well does this fit folks with smaller heads? I'm about 55cm head circumference (measured from the back of head bump to about 3'' above eyes) and i see this claims to fit 53-60. Most helmets i've seen (petzl, mammut) have a 5cm rance. Is this a bit of a stretch? I run pretty hot and often ski without a touque so I'm hoping it fits/adjusts well

Five Stars, mainly because you have no choice in the matter: if you need (for ISMF compliance) or just want (for personal safety), a dual-cert helmet, the competition is almost 2x the weight.
I found the fit to be instantly comfortable yet secure, thanks to both the lack of weight on my head combined with the highly effective yet very simple adjustable strap on the back of the head. A few extra foam pads are included in case you want to fine tune the fit a bit more.
Also included are a storage bag and a helmet carry for securing the helmet to the back of your pack on long warm approaches (although I've never felt the need for this feature since any helmet has its own carry system in the form of the chin strap & buckle).
Vents though are rather minimal, as its typical (and perhaps inevitable) to meet the standards for both climb & ski.
The exterior clips are of the double-duty variety as they also serve as the anchors for the strap system. They seem fine for a headlamp strap or cord based on some indoor tests. For goggles, the clips seemed to provide decent security in the back, although I haven't tested this for real since I wear goggles once a year or so at most. A couple pairs I tried inside also fit fine in front. More importantly, something about the shape of the helmet is inherently accommodating for a goggle strap, as the strap didn't seem to have a tendency to slip up or down, unlike many other climbing-only helmets I've tried.
As for looks, stunning. As in, stunningly horrendous! Although Grivel does not receive any ingenuity points since the Duetto is simply a beefed-up first-generation Sirocco (i.e, 100% EPP design), the lack of any taper at the bottom of the helmet sides make the helmet look even wider than it really is. I surprised that my measurements showed the Duetto as merely ~2.5mm thicker than the Sirocco, as it looks more like 25% thicker. The Duetto avoids the Crystal Dome look of the first-generation Sirocco, and my muted-grey Duetto stands out far less that the auto safety orange of the first-generation Sirocco, yet to the Duetto still comes across as downright bizarre. And by contrast, my climbing-only BD Vapor and dual-cert Camp Speed Comp are wonderfully fashionable compared to the Duetto. Fortunately, anyone who laughs at your will stop laughing immediately once you let the person lift up the helmet!