1.The carborundum grinding wheel, super hard and wear resistant
2.USB rechargeable type charging time:2hours Runing time:3.5hours
3.The super large torque motor better than traditional motors , product keeps constant RPM according to set of speed.Two speed of rotation, ＂LOW＂ and ＂HIGH＂.
4.The indicator light is blinking red light when charging and lights off once it is fully charged
