I find Mammut runs on the small side and recommend sizing up if you're in between.

Does Mammut fit small?

Sizing for mammut is very odd depending on the jacket and year it was made... current line is more typical of normal sizing but the old stuff ran really small(very euro cut).

Do Mammut boots run true to size?

Mammut said typically their boots fit true to size and their customers usually purchase their normal shoe size, he did say some people size up though. I plan to go back to Feathered Friends and try a few more sizes on.