Features： 1、Variable Speed Throttle Control: The wind mill pen set has variable speed throttle control, the speed can achieve 58000 rpm, and has an automatic closing lever. 2、Multi Function: Equipped with a high speed rotating wind milling pen set, which improves work efficiency and smooth work; and also has a rear exhaust to prevent debris from flying, and low noise. 3、One Handed Operation: The pneumatic grinder is small in size and light in weight, and the pen shaped design makes it easy to use with one hand. 4、Ergonomic Design: This is a pneumatic grinder designed with the ergonomic principle of the hand, which can make your operation more comfortable. 5、Scope of Application: The wind grinding pen set is very suitable for cleaning and polishing jewelry, transplanting cylinder heads, molds or any hobby and craft purposes. Specification： Item Type: Air Micro Grinder Kit  Material: Stainless Steel + Plastic Purpose: Pneumatic Grinding Machine Speed Per Minute: 58000rpm Chuck Specification: Approx. 3mm / 0.1in Wind Mill Pen Diameter: Approx. 16mm / 0.6in Diameter of the Head of the Wind Mill Pen: Approx. 10mm / 0.4in Inlet Diameter: Approx. 8mm / 0.3in Hose Diameter: Approx. 7mm / 0.2in Plastic Hose Diameter: Approx. 14.5mm / 0.6in Recommended Air Pressure: 90 PSI Average Air Consumption: 60L/min Package List： 1 x Mini Air Grinder with Hose 10 x Grinding Head 2 x Chuck 1 x Oil Bottle (without Oil) 2 x Small Wrench 1 x FNPT Connector 1 x Storage Box 1 x English User Manual