This SCT Manufacturing Glock® Compatible Full-Size Frame is going to change the way you build pistols. It is the only frame at this price point packed with this level of features. This is a serialized frame with shooter-oriented ergonomics. Installed over-molded rails that are ready to build. They are made with an industry leading proprietary polymer blend and compatible with Glock® Gen 3 17,22, and 31 frames. Other Features Include: Serrations and index point on trigger guard to help control recoil Serrations on top of beaver tail reduce glare GEN 5 Style Slide lock (spring included) Flared mag well Thumb Accelerator pad Advanced contour grip with aggressive texturing Picatinny rail (not a Glock® rail) “MIL-STD 1913 Picatinny” High beaver tail with low profile bore axis Grip angle is the same as Glock® Slide stop guard Larger trigger guard for better access with gloves Recessed contoured mag release area for faster mag changes Multi caliber- Compatible with compact 9mm, 40 cal, 357SIG Mag Well compatibility Includes locking block installed Weight – 3.6 oz. Without Locking Block