Tritium Pro Night Sights retain the brightness and durability of Truglo's original green Tritium night sights with added Pro features: a quick and accurate U-notch design, an angled rear sight edge for emergency one-hand operation, and white Focus Lock ring on the front sight for even faster focus. This Tritium Pro sight set is compatible with Glock 17,17L, 19,22,23,24,26,27,33,34,35,38,39 (excluding MOS models).