The Hawke Sport Optics XB320 Crossbow Scope is designed to withstand the rigours of crossbows with reticle systems guaranteed to make you a better shot! Distance aim points are calibrated to match the crossbow ballistics. Adjust speed selector (magnification) to match bow speed. Calibrated to work on crossbow speeds from 280 - 440 fps. Illuminated aim points represent 1.5 inches across at their respective distances out to 60 yards when on 425 fps (5x magnification) only. FeaturesCapped Low-Profile Turrets30mm Mono-Tube ChassisIllumination1/2 MOA Low-Profile Fingertip TurretsFixed Parallax At 45 Metres11 Layer Fully Multi-Coated LensesHigh Torque Zoom RingFast Focus EyebellSuitable Speeds 280fps - 440fps