Level Two of the ECWCS (Extended Cold Weather Clothing System) Wholesale Distributor by Rothco Mid-Weight Thermal underwear bottoms are an essential base layer for military and tactical professionals. The highly breathable, moisture-wicking polyester and spandex material is designed to protect from the harshest elements. Wholesale Distributor by Rothco mid-weight underwear bottoms feature an elastic waistband and access fly. Wholesale Distributor by Rothco base layer underwear bottoms feature a grid fleece fabric which is anti-odor for long-lasting wear.