This sight is smaller than the former N-cell battery sight and runs on a single 123 battery. It also has a longer battery life than the N-cell style sights. Smaller, lighter and always fast with three reticle options. With the new single battery configuration, the XPS allows more rail space than ever, leaving more room for rear iron sights or NV mount.- Single transverse 123 battery to reduce sight length - Shortened base only requires at most 2 3/4 inch of rail space compared to the 4 inch N battery sights - Battery cap and latch are eliminated and replaced with a simple O-ring, tethered cap; better sealing is achieved - Battery compartment is now separated from the base to allow it to hover over the delta ring of the rifle - Average battery life at brightness level 12 is roughly 500-600 hours, 3X battery life of N cell sights - Reticle: 65 MOA ring with 2- 1 MOA aiming dots.