The Army's permanently fire resistant Nomex aircrew trousers were introduced in 1968 and had two hip pockets, two slash front pockets, two shin pockets with zip fasteners and two large thigh pockets with inside leg zip closures. The right thigh bellows pocket contained a zippered knife pocket, which was accessible from the outside leg and was used for storing an emergency marker panel. The trousers, which were issued with a matching shirt, also featured Velcro ankle fasteners and a front half belt with side adjustment straps.1
1. Support To United States Army In Vietnam - Clothing & Organic Materials Vol II (United States Army Material Command Aug 1968)