Extreme Precision Swivel Tilt Lever Bipod with 9" to 13" Adjustable Spring for Tactical Airsoft Air Rifle Gun Hunting Shooting Fits all Standard 20 mm Picatinny Rail. The Swivel Tilt can allow you to set the gun level, it is even excellent when shooting in rough uneven ground . Quickly Attach to or Detach From the Rail Mount Using Existing Quick Release Screw. Legs can be Folded Forward or Backword. Made of durable, light-weight aluminum.