The Hot Chillys Kids' Pepper Bi-Ply Bottoms are made with two layers of fabric connected back-to-back with open spaces between the layers to trap and hold warm air. These kids' long underwear pants are knitted with MTF soft spun polyester fibers that transport moisture away from the skin to keep you warm, dry and comfortable. Pepper Bi-Ply is a tried-and-true favorite choice for soft, comfy children's thermal pants while protecting against the cold. | Hot Chillys Kids' Pepper Bi Ply Pants