Air needle scaler for cleaning and descaling work, removing rust, paint and corrosion etc and is an essential tool for mechanics, ship workers as well as bridge workStraight design with a lever arm throttle for easier use. Stroke Speed: 4,000 bpm. Needle Stroke: 0.94 inchesHandle design insulates against cold air and vibration. Sound Pressure Level: 88.7 dB. Vibration: 3.8 m/s squaredAir exhaust in the handle to protect against cold air. Air Inlet: 1/4 inch. Minimum Hose Size: 3/8 inchSupplied complete with 12 needles. For use with 0.12 inch diameter, 4.96 inch long needles