Introducing the Pearce Grip Extension for Glock 20, 21, 40 GEN 3-5. This extension replaces the magazine floor plate adding 1" in grip length to Glock factory M20,M21,M29,M40 and M41 magazines. This does not alter the capacity of the magazine. This unit works on all 10mm and 45ACP Magazines except 10 round Glock 30 magazines. Approximately 1/2" longer than the PG-29 grip extension. FeaturesThese increase grip length and control of M20,M21,M29,M30*,M40 and M41 magazinesThey are made from High Impact Polymer and withstand temperatures from -20 F to 250 F. Notes: These units will work on third, fourth and fifth generation Glock models.