These are extreme cold weather boots that are used in the US Military. The boots help protect the user when operating in extreme cold weather environments. They have a thick rubber sole, laces, and full zipper. Also, they cover the wearers thigh. The upper material is water and wind resistant. There are thick wool insoles for added insulation. The boots, aside from insole, are not insulated.
These boots are meant to be worn with boot liners and thick socks! As a result they are oversized!