To consider a gun to be great, it must be reliable day and night. Providing a consistent green glow, Rival's tritium night sights ensure accuracy in low light and even complete darkness. In daylight, a large orange dot and rounded notch design increase speed and accuracy. The frame was CNC-machined of stainless steel construction, snag resistant design. Designed to fit all double stack 9mm Glock models. M.O.S. models are intended for M.O.S. slides and other slides with a mounted optic to provide proper co-witness through the optic.