Benjamin Trail NP Mark II Air Pistol Nitro gas piston Breakbarrel Rifled steel barrel Picatinny rail under barrel Single-shot Fiber optic front and rear sight Adjustable, removable rear sight 11mm dovetail rail Tactical, synthetic frame Includes removable cocking aid Up to 650 FPS with alloy, 525 FPS with lead Here are the benefits of the Nitro Piston: Smoother cocking Smoother shooting No spring torque No spring fatigue, even if you leave it cocked for hours Functions perfectly in cold weather Lasts longer than a metal spring