Heat Holders® Men's ULTRA LITE™ Base Layer Bottoms are a light weight thermal base layer ideal for everyday cold. DUAL BRUSHING Supersoft HeatWeaver® yarn is carefully brushed both inside and out to maximize warmth and softness. PERFECT STRETCH Our knitting technology and attention to detail produce the perfect stretch for freedom of movement and fit. FLAT COMFORT SEAMS Our carefully finished flat seams minimize bulk to create a comfortable non-chafe fit, perfect for layering. ODOR MANAGEMENT Odor management technology helps keep you fresher and more comfortable. Matching Tops also available.