Feature: 1. Improve Accuracy: Laser bore sight emits a straight red laser beam, providing an accurate reference for zeroing in on your target. 2. Clear Beam: Clear and bright red laser, which is not easily affected by weather and has longer sighting range, allows you to accurately aim at the target even in low visibility. 3. High Adaptability: The laser calibrator is equipped with 5 caliber adapters, suitable for any firearm and optic with diameters ranging from 0.22 to 0.50. 4. Lightweight: Laser calibrator is lightweight and durable. The compact design allows for convenient storage and easy carrying. 5. Easy to Use: Simply choose the caliber adapter and place the laser bore sight unit in the muzzle, which is convenient for your use. Specification: Item Type: Bore Sight Kit Material: Aluminum alloy Use: For firearms and optics from 0.22 to 0.50 caliber Shipped with matching battery Battery Type: 3 x 1.5V LR44 Single Battery Capacity: 160mAh Length: Approx. 155mm / 6.1in. Package List: 1 x Red Laser Bore Sight 3 x Button Cells 1 x Electronic Compartment 5 x Adapters 1 x Wrench 1 x Screwdriver 6 x Screws 1 x Instruction Manual