Trijicon 3 Dot night sight sets are designed and assembled with the optimum combination of strength and safety. The patented aluminum cylinder and sapphire lens construction cannot be equaled. The brightness obtained from the tritium content is focused through the sapphire lens to give the maximum possible illumination. Because the Glock sight blades are machined from steel rather than cast, their strength is unsurpassed. Trijicon Glock night sights are the brightest, strongest and safest. Green lamps are warranted for 12 years from the date of manufacture. Details: The TRI-GL04 3 dot green frot & green high rear night sight set fits Glock models 20, 21, 29, 30, 31, 32 and 37.