SIG Sauer is dedicated to keeping your favorite handgun in the running with its quality magazines. Starting with the body these magazines are made with a stainless steel body. With this strong base, these mags are designed to last. This is further assisted by the impact-resistant polymer base plate. For keeping track of ammo the magazine also comes with a high-visibility follower and witness holes on the back. Specifications and Features: Caliber: 9mm Luger Capacity 30 Rounds Stainless Steel Body High-Lubricity Finish for Reliable Function Rear Witness Holes in Increments of 5 to Display the Remaining Rounds in the Magazine Stainless Steel Body High Visibility anti tilt follower Polymer Sleeve Black and Coyote Tan Finish