Product Overview Jentra frame plug for GEN 4 Glock models: 20, 21 & 41. JP-7. This plug will not work with the backstraps installed. Reviews (1 review) Write a Review 1 Review Hide Reviews Show Reviews 5 Jentra Plug Fits Gen4 Plug G20,21,41 Posted by Unknown on 31st Jan 2022 Fits great and will help keep foreign material out of the firearm. No fuss ordering/shipping. Thanks, RYG.