Glock Backstrap Set G29, G30 (Gen4 only); Black The GLOCK Modular Back Strap System enables the pistol to adapt to an individual shooter's hand size. Installing and removing the back straps is
Glock Beavertail / Backstrap Set, OD Green (G19, G23, G32 - Gen4 Only): MGW
Glock Gen 4 Beavertail Backstrap Kit G20,21 - Glockparts.com
Amazon.com : Talon Grip for Glock 19,23,25,32,38 (Gen4 Med Backstrap) Black Granulate - 111G W/Free Sticker - Johnson Enterprises, LLC : Sports & Outdoors