Promag Handgun Drum Magazine Black Polymer Fits Glock Models 21&30 .45 ACP 40/rd

40-round drum magazine Fits the Glock Model 21 and 30 .45 ACP Drum housing constructed of a proprietary DuPont Zytel based polymer Magazine spring formed from heat treated stainless steel wire Injection molded magazine follower Over molded stamped steel feed lips and magazine catch Made in USA