The Hot Chillys® MTF Micro Elite men's bottoms feature the MTF Micro Elite Chamois fabric, a blend of Bio-Silver® polyester, micro-denier polyester, and Lycra® spandex which fits like a second skin, adapting to your movements to create a warm and comfortable base layer. Bio-Silver® fabric prevents bacteria, fungus, and odor from accumulating, giving you a fresh and clean feel every time.