Material: high-quality aluminum alloy material, light and durable. Installation: Connect directly to the braided/picatinny dovetail to ensure that the holes and crosshairs are aligned at a glance, and can be placed in the front, back, or lower range to make sure your range is absolutely horizontal. Suitable for: Compatible with 20mm track Picatin guide rail. Due to the difference of light and screen, the color of the product may be slightly different from the picture.