This laser calibrator is made of high-grade aluminum alloy material, which is lightweight, high in strength, corrosion-resistant, and designed for a long service life. The product includes a full set of accessories, ready to use upon arrival and convenient to operate.Features: - Constructed from high-grade aluminum alloy for durability and long-term performance - Infrared calibration with laser light that provides bright, clear visibility over long distances, aiding in accurate alignment - High-precision design allows for easy and accurate adjustment of straight tubes - Simple and sleek battery compartment design; the tail cap opens by unscrewing for easy access and practical use How to Use the Collimator: 1. Measure the inner diameter of the tube and select a suitable adapter (8 small black heads included). 2. Use a cross-head screwdriver to attach the adapter to the tail of the collimator tube. 3. Ensure the collimator is aligned properly by tightening the battery compartment and switch to maintain a straight pen body. 4. Secure the adapter and insert the tail tube into the target tube, ensuring the switch side faces upward. Mount the device and align it with the sight or scope. 5. Adjust the sight or scope until the laser dot is parallel to the reference point for accurate calibration. Includes: Laser calibrator, 12 adjustable adapters, red laser light