Great Upgrade For target practice or the weekend battle at your local paintball field. Connects to any weaver rail. Weaver Mount will easily clamp into your Cronus Marker rail. Fully adjustable for Windage and Elevation On/Off Rear Cap Switch is easily turned On or Off with your trigger finger All Aluminum Construction 635-655nm Red Laser Beam <5mw Specially designed Weaver style mount Standard on/off cap switch Includes 3 AG13 Lithium type batteries and mounting tool Dimensions (inches): 1.61Lx1.04 Wx1.19H Weight: 1.2oz. with batteries