The truglo crossbow red dot sight when shooting at close or medium ranges, a red dot sight is a great option for crossbow hunters.The 30mm traditional offers unlimited eye-relief, a wide field of few and a compact design that are not available in magnified optics.Features descending diameter dots reticle for multi-distance shooting (smaller dot for longer shots).Battery: CR2032Magnification: 1xObjective: 30mmField Of View: 68 ft @ 100 ydsEye Relief: UnlimitedDot Size: 5 MOA/3.5 MOA/ 2 MOATube Diameter: 30mmLength: 3.82"Weight: 7.0 ozReticle: 3 Red Descending Diameter DotsAdjustment Size: 1.0 MOAProofs: Water/Shock Resistant/Fog ProofWindage Elevation: Adjustable