Holsters can be made from canvas, or even lace, but mostly you will find leather and Kydex. Leather is the hide of animals, either softened to fit the contours of your body or stiffened to hold the gun firmly. Kydex is a thermoplastic acrylic polyvinyl chloride (PVC) composite. It is tough and rigid and can be manufactured to fit the exact specifications of your gun. Kydex is water and sweat-resistant, scratch-resistant, and unlikely to stretch or shrink.