This hand held Pneumatic Capping Machine is mainly used to the tighten ot loosen caps. It is easy to carry and it's adjustable clutch can effectively avoid the cap damage & reduce the wear of the internal plug. Once the cap is tightened,the chuck will stop rotating,so that you can move to the next operation. It is suitable for variety of high strength bottle caps which is in 10 to 50mm diameter. It can cap 30 to 90 bottled per min. This one is specialised for caps with security ring diameter 28 to 32mm & 38mm... This machine is pneumatic because it uses air compressor to operate