There's nothing quite like a gaiter to keep you warm on a descent. The Polartec® Neck Gaiter regulates heat to keep your neck warm on those chilly rides, and once you hit the downhill just pull it up over your chin or nose and it'll stay there, extending those warming benefits where you need it most. 

Polartec® fabric actively regulates heat to keep you warm and dry
Designed to stay up during rough downhill and out of the way when you need to breathe hard during a climb
85% Polyester / 15% Elastane