Designed for patrol and tactical operations, the rugged P4Xi scopes offer clear images and a fast-action reticle to tackle every day use or sudden action. The P4Xi 4-16x56 is a medium range scope with 34mm tube, an illuminated front focal plane Special Competition Reticle (SCR™) and side parallax adjustment. Steiner 4-16x56 SCR Zero Stop FFP Tac Knobs 5221