Zengi QD Quick Detach Harris Bipod Adapter for Picatinny Weaver Rails Bipod or Sling Swivel Stud Airsoft or Paintball Universal Base , Fits for 20mm picatinny Rail / Weaver Rail Stud Is Designed For Sling Swivels Or Stud Mounted Bipods. QD Lever Lock For Quick Install/Uninstall Made from Extra Durable 6061 Aircraft Aluminum alloy with Black Matte Finish Supply with Allen Wrench