This 27-round magazine from ProMag is compatible with Glock G22 Glock 23 and Glock G27 pistols.The magazine body is constructed of a proprietary DuPont Zytel-based polymer with a full-length steel internal insert stamped and welded just like the factory magazine.In addition it has a spring made from heat-treated chrome silicon wire and an injection-molded magazine follower for increased longevity.ProMag Glock G22/G23/G27 Magazine40 S&W Caliber27 Round CapacityCompatible withGlock 22 modelsGlock 23 modelsGlock 27 modelsOrder your ProMag Glock 40 S&W magazine online today!Shopping for ammunition? Score big savings and fast shipping when you shop our large selection of cheap bulk ammo for sale.Score big savings and fast shipping on all our best-selling ProMag rifle and pistol Magazines available online at Ammunition Depot.