1、UPGRADE TECHNOLOGY: The core component of this pneumatic pen is tungsten alloy gear set, which has superior wear resistance and long service life 2、FAST AND EFFICIENT: The bearing of the pneumatic pen can withstand the ultra high speed of 70000rpm, which improve the grinding speed and efficiency, stable and reliable 3、LIGHT AND PORTABLE: This pneumatic pen is small, lightweight and has a pen shaped design that allow you to use with one hand, making it ideal for use in some narrow areas. Easy to load and unload, easy to carry 4、MULTIPLE USES: This pneumatic pen can be used for accurate grinding of various metals as well as cutting plastic, stone, wood, etc., useful and practical 5、APPLICABLE SCENARIO: You can also use a miniature grinder for grinding, polishing, cleaning accessories, rotors, backplanes, brake pads, cylinder heads, bases, and other applications