The Strike Industries magazine release for the Gen 4-5 Glock is a new modular upgrade for the Glock Gen 4 and 5. Included are two push buttons that are easily interchangeable. Both button faces are CNC milled from 6061 Aluminum, with mag release internal mechanism made from high density polymer that provides smooth ejection. Features: Includes (2) interchangeable 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 cut-outs and polymer pistol body