The Glock 37 Gen4, in .45 G.A.P., introduces revolutionary design changes to this quantum leap forward in big-bore technology, Glock’s answer to muzzle flip and high-velocity recoil. The modular backstrap design lets the user adapt the grip to hand size, and the frame surface exhibits the scientifically-designed Gen4 rough textured technology. This model features a dual-recoil spring assembly that substantially increases the life of the system, and the enlarged reversible magazine catch easily accommodates left- or right-handed operators. The Generation 4 frame retains the Glock accessory rail for accessory attachment.