Airsoftjunkiez shows you hot to install the Bullgear CNC HPA Hop-Up for Tokyo Marui MP7 Series in this video. You can get this right now at their onlinestore... "Detailed video to help with the installation of the MP7 Bullgear Hop Up onto Airsoftjunkiez or Bingo HPA chassis to give your MP7 improved consistency and range."