Rothco's Gen III Silk Weight Underwear Bottoms are level 1 of the E.C.W.C.S. system. These underwear bottoms are highly breathable, complete with moisture wicking properties to keep you dry. Anti-microbial and anti-odor protection keep the bottoms fresh by keeping bacteria and bad odors from forming. The silk weight underwear bottoms have an elastic waistband for a comfortable fit as well as an access fly. The Gen III Silk Weight Bottoms pair well with the matching Level I Silk Weight Tops and are great for layering with other ECWCS items for extreme warmth in cold climates.  Rothco Gen III Level I Underwear Bottoms are part of ECWCS (Extended Cold Weather Clothing System) which provides extra warmth in cold climates.