The Dead On 8 stage expansion chamber helps remove liquid co2 from the air line before the valve system of the marker. Made from 6061-T6 aluminum. Choose from Black, Blue, Green, Red, Silver Performance Enhancements: The ability to remove liquid co2. More consistant FPS shoot to shoot. Less spikes in velocity. Compatibility: Universal ASA threads. Installation instructions: Tools required: Open end wrench for your air line fitting. 1. Remove tank. 2. Remove other expansion chamber or reg or line adapter as per spyder. 3. Install X-core. 4. Install air line fitting, as tightening fitting keep in mind of incoming air line direction. 5. Install air line.