The H2S Inferno Proclava provides the warmth you're looking for. Designed not to interfere when wearing a helmet you'll love the way the Inferno proclava brings your helmet and jacket together. The Inferno provides all of the warmth you would ever want. The heavy fleece will use up inside helmet space so plan accordingly. Wear it alone to get superior protection from the cold.
Features:
80% micro fleece, 20% Lycra
Lycra top provides comfort without affecting helmet sizing
Double layer fleece on neck and face
Single layer fleece on chest and shoulders
Flat-lock seams offer improved comfort and fit under helmet
One size fits most
Lycra top won't affect your helmet size, polar fleece neck and chest keep you extra warm where it counts. Sounds like a winner to me!