Feature: 1. Connect Device: With this helmet side rail, you can attach lights, lasers, cameras or other devices to helmet by using standard arc rail dovetail adapter (not included). 2. Helmet Accessory: The helmet rail is a great accessory for your helmet, which can be firmly fixed to your helmet and is not easy to fall off. 3. Suitable for FAST helmet: Helmet side rail adapts for FAST helmet, use matching screws for easy installation and easy use on the for FAST helmet. 4. ABS Material: The helmet rail bracket is made of ABS material, which is sturdy and durable, and has a long service life. 5. Used For: This rail mount helmet kit is used for outdoor CS protective equipment helmet. Including screws and spacer, it is easy to install onto helmet. Specification: Item Type: Helmet Side Rail Product Material: ABS Weight: Approx. 153g / 5.4oz. Package List: 2 x Helmet Rail 4 x Screw 4 x Spacer