Our ultimate, award-winning mid-layers, the Coefficient fleece collection is ready for the mountains. Built with Polartec® Power Grid® fleece designed for high output activities, the Coefficient breathes while on the move, and wicks moisture when things heat up. The minimal slim-cut profile layers easily and added features like an under-the-helmet hood make the Coefficient hyper-versatile for any mountain adventure.

Black Diamond photographer Christian Adam wearing the Coefficient LT Hybrid Hoody in Iceland.
The Black Diamond Coefficient LT Hybrid Hoody.
A climber wearing the Black Diamond Coefficient Hoody.
Black Diamond Athlete Hazel Findley climbs wearing the Black Diamond Coefficient Hoody.

Technical midlayer insulation ideal for everything from chilly cragging days to big mountain missions.

Shop Women's Fleece
A skier zips up their shell Jacket wearing the Black Diamond Coefficient Hoody as a base/mid layer.
A climber wears the Black Diamond Coefficient hoody while climbing in Little Cottonwood canyon, UT.
A climber wears the Black Diamond Coefficient hoody while climbing in AZ.
A Skier boot backs up a mountain wearing the Black Diamond Coefficient Hoody.

A midlayer for anything from ski tours to alpine ascents

Shop Men's Fleece