The Rho Heavyweights – our warmest base layer tops – are made for cold days and mixed output. On the move, the Polartec® Power Stretch® Pro stretches for outstanding freedom of movement. During rest phases – or when it gets really cold – the fleece’s soft brushed interior traps heat to keep you warm. The fleece’s durable nylon outer has a smooth face for comfort under layers, the tall collar extends warmth, and the deep front zipper aids heat dump and makes on-and-off easier.

The Rho Heavyweight Zip Neck was previously the Rho AR Zip Neck.

Size and Fit Tips: Fitted Fit - This trimmer fit is patterned to stay close to the body through the chest, waist, hip, and thigh. Its low profile eliminates bulk, moves with the body, and fits comfortably under outer layers. Be sure to reference our new sizing charts before you check out.