13-ounce, flame-resistant 100% cotton duck, it features a quilt lining, a high back with flame-resistant elastic suspenders and high temperature nylon center-release buckles. They also have a chap-style double front for durability, flame-resistant melamine button at waist, multiple tool and utility pockets, ankle-to-mid-thigh brass leg zippers with Nomex® zipper tape and protective flaps and arc-resistant snap closures.