2IN1 – Thermo underpants for men – made with two layers:  Functional polyester inside and Cotton outside sewn together with a polyester thread.  A unique knit creates a diamond-like air pocket that insulates heat.  2IN1 apparel protects against the cold and does not inhibit movement, so it is ideal for work and active lifestyles. Material: Thermowave's Functional Polyester is suitable for a variety of activities in chilly-to-cold weather conditions. Made from 100% functional polyester yarns, this fabric provides an exceptional moisture evaproration function. In addition, featuring a unique knitted fabric structure, Thermowave's polyester garments feature great warmth insulation, are light, soft, and have an excellent body fit. All of these benefits, coupled with very easy care, make our polyester garments a perfect choice for intensive activities in lower temperatures. All Thermowave's functional polyester garments are applied with Silver-ion finishing to kill-off the bacteria responsible for the uncomfortable smell. Made with dual-layer technology; Unique knit creates a diamon-like air pocket that insulates heat; Protects against the cold; Does not inhibit movement. Suggested activity: Hunting, fihing, and work. Composition: 100% functional polyester inside, 100% cotton outside.