This is not a Glock Factory Product, it is an after market Product; Includes two interchangable button heads; Agressive texturing on push pad to prevent slippage; Hybrid design with anodized aluminum and polymer body bar; Main body designed with polymer to minimize wear and tear on magazine retention cutouts and polymer pistol body; Fits: Gen 4 and Gen 5 Glock 17, 19, 22, 23, 26, 27, 31, 32, 33, 34, 35, 37, 38, 39; Does NOT Fit: Glock 36, 42, 43, 43X, 48