Sig's Romeo3Max is a compact, open reflex sight features a 30mm wide, round lens for superior field-of-view, a special red-notch filter for vivid red dot and unrivaled optical clarity, with a 3 MOA dot size for rapid target engagement, twelve illumination intensity levels, MOTAC activation, and up to 20,000 hours of runtime. It is constructed of aluminum and comes with a low-profile Picatinny mount.