Utilizing a dot-over-dot configuration, their i-Dot sets have an extended square-notch rear for increased sight radius with a glare-reducing undercut rear face. The i-Dot sights provide a quick and easy vertical sight alignment, making it an excellent choice for all shooters. Features : "Green tritium" .140" wide LumiGreen outline front" "Green tritium" .165: wide notch rear" GLOCK is a registered trademark of GLOCK Inc. 3CR Tactical is not affiliated with, endorsed by, or sponsored by GLOCK Inc. Any reference to GLOCK products is for identification and compatibility purposes only.