When the sun goes down, don't get left in the dark. TruGloA(R) Tritium Pro Sights transition from standard white dot sights during the daylight to glowing green dots in the darkness. Tritium doesn't need batteries and never needs to be charged, so these Sights are always "on," ready to provide bright targeting when you really need it. Both the Front and Rear Sight are CNC machined from alloy steel, and feature a nitride fortress finish for exceptional corrosion resistance. An orange Focus-Lock ring on the Front Sight helps you pick up your target quickly and easily, encouraging your eye to rapidly focus. The compact design maintains the factory sight radius and ensures fit with standard holsters. Fits Glock M.O.S. 17/17L, 19/19X, 22, 23, 24, 26, 27, 33, 34, 35, 39, & 45 Includes Front Sight and U-notch Rear Sight Tritium inserts transition from standard white in the daylight to glowing orange dots in the dark Tritium doesn't require batteries and never needs to be charged-it's always on Orange Focus-Lock ring helps you pick up the Front Sight CNC-machined alloy steel construction with nitride fortress finish Flat serrated surface on Rear Sight allows emergency one-handed cocking