The Assos Ultraz Winter Skin Layer Long Sleeve P1 is the warmest base layer Assos makes. It is built for the coldest, most extreme winter rides. Its ultra-high collar extends coverage for enhanced protection, while the blend of merino wool and synthetic fibers offers unmatched insulation and natural thermoregulation. This textile provides a soft, itch-free feel with high elasticity to move with your body and maintain a next-to-skin fit. Its fit traps warmth and wicks away moisture, keeping you dry and comfortable. With permanent odorControl from carbon fibers and merinos antimicrobial properties, you will feel fresh for the whole ride. The Assos Ultraz Winter Skin Layer is an ideal choice for cold weather rides.