Front sight FOCUS LOCK ring for even faster focus Quick and accurate U-notch Design Angled rear sight edge for emergency one-hand operation Assembled in USA with quality Swiss Tritium for maximum brightness Unmatched visibility in low-light shooting conditions or complete darkness Utilizes quality Swiss tritium for maximum brightness Glows-in-the-dark no batteries or light exposure required FORTRESS FINISH provides a permanent protective coating for maximum protection Snag resistant design / fits standard holsters Simply put, TRUGLO manufactures bright ideas. When TFX PRO sights immediately took off and gained critical acclaim, the world of TRITIUM night sights needed a similar upgrade. Starting with the brightness and durability of the original TRITIUM night sights, the PRO level now features to give you the advantage when you need it the most.