The Meprolight Tru-Dot Night Sights are combat-proven self-illuminated sights designed for HK USP pistols in 9mm .40 and .45 caliber. These tritium-powered sights provide superior target acquisition in all lighting conditions without batteries or switches.Meprolight Tru-Dot Fixed Sight SetFits HK USP Full Size pistols (9mm .40 .45)Green and orange tritium inserts for high visibilitySelf-illuminated - no batteries requiredCombat-proven design trusted by leading firearm manufacturersHighly durable construction for long-lasting performancePerfect for daylight low-light and nighttime conditionsUpgrade your HK USP with these professional-grade night sights that dramatically increase hit probability under low-light conditions. Always ready for action with reliable tritium illumination that never needs charging or replacement batteries.