The ProMag Magazine for the Glock 17/19 pistol features a magazine body constructed from a proprietary DuPont Zytel based polymer. The follower is injection molded and the magazine spring formed from heat treated chrome silicon wire. Features50-round drum magazineFits the Glock Model 17 & 19 9mm pistolsMagazine body constructed of a proprietary DuPont Zytel based polymerInjection molded magazine followerMagazine spring formed from heat treated stainless steel DISCLAIMER: This product is not manufactured, authorized, endorsed, or warranted by GLOCK. GLOCK does not warrant or represent that this product is compatible with GLOCK pistols.