Fits Sig Sauer models calibrated for 9mm and .357SIG, including P225, P226, P228, P239 and P320 (Excluding P938). The Trijicon HD XR night sights were specifically designed with the ever evolving challenges of law enforcement agencies in mind. Building on the features of the current HD night sights, the Trijicon HD XR night sights are for the next level of advanced target identification and engagement at increased distances. A thinner front sight post allows shooters to have a larger field of view which further enhances the ability to identify targets, expedite engagements and see location of hits on target at longer distances. Pistol shooters that need the advantage of a more precise engagement in any light can count on the Trijicon HD XR night sights. Green tritium lamps are warranted for 12 years from date of manufacture.Features:Expanded field of view and a precision sight picture for longer-range engagements - thin front post (0.122 inches width) promotes a larger field of view for fast target identification and engagement at longer distancesEnhanced front sight acquisition in bright, transitional and no light situations1-handed slide manipulation - steeply hooked front surface to assist in an emergency, 1-handed slide manipulationInstantly visible sight picture in no-light and low-light situations - Tritium phosphor-filled glass lamp illuminates sights for high visibility in all lighting conditionsEnhanced protection from heavy recoil and harsh cleaning solvents - Tritium gas lamps are contained within protective aluminum cylinders and have additional silicone rubber cushioningEvenly distributed light from Tritium lamps - each Trijicon Tritium lamp is capped with a sapphire jewel that helps evenly distribute the light and also acts as an additional layer of protection from puncture and cleaning solvents