Based on an optical illumination patent, the Mepro ft Bullseye is an extremely small (smallest optical sight in the world), low profile, optical pistol sight. Similar to reflex sights, using the Mepro ft Bullseye provides the shooter with an aim point in the form of an illuminated dot and circle Bullseye. Shooters can enjoy intuitive and fast target acquisition. The fiber-optic tritium combination enables instant and accurate shooting in all lighting conditions with no batteries needed. The fiber-optic used in bright light or day shooting, and the premium-grade tritium provides instant illumination at night or in low-light conditions..