This is a Glock 22/23/27/35 .40 S&W 50-round magazine from KCI. This 50-round drum magazine features a clear polymer back for keeping an eye on magazine capacity, along with a set of finger tabs to make reloads quick and easy. Internal heat-treated chrome silicon wire spring ensures maximum reliability and smooth feeding. KCI drum magazines deliver maximum capacity and impressive quality for the world’s most popular pistols—all at a price that’s hard to beat. Engineered for reliable performance and superior quality, these KCI magazines are the perfect upgrade for your Glock magazine. All KCI magazines come with a lifetime limited warranty. Grab a few KCI drum magazines and get the ultimate in capacity for maximum fun and firepower with your Glock or Glock-compatible carbine (including Kel-Tec Sub 2000 and Lone Wolf AR-15)!