The Magpul GL Enhanced Magazine Well is a high performance purpose built Glock frame magazine well. Designed to fully enhance and ensure positive magazine insertion in high stress scenarios. Sleek and ergonomic design features also provide excellent concealment while ensuring minimal printing to the users clothing. Ramp and edge geometry allow for the positive and flawless removal of faulty or stuck magazines during reloading or immediate action events. The Magpul GL Enhanced Magazine Well is optimized for use with standard capacity Glock factory magazines, Magpul GL magazines, and a variety of aftermarket floorplates and extensions that are available for both. Recent generations of reduced capacity (10 rd) factory Glock magazines have several dimensional differences which may interfere with any magazine well, including the Magpul GL Enhanced Magazine Well. Some large aftermarket floorplates may also interfere. The Magpul GL Enhanced Magazine Well for Glock 17 Gen 4 and Glock 19 Gen 4 are not compatible as delivered out of the box with optional factory Glock Modular Back Straps. While end user modification is minor and may be attempted, it is taken at own risk. Due to inherent variances in Glock frame production, if an excessively tight fit is experienced during the installation of an Enhanced Magazine Well that requires excessive force it is recommended that a competent and professional gunsmith be utilized to complete the installation. Made in U.S.A.