... has many specialties as follows: light and pen shaped design, small volume, high speed of rotation, low noise, large torque, low ... subject:01.rotor 03.middle crustl05.blade 06.small axis circle07.bearing box 08.small bearing(motor bearing)09.121N-head 10 ... piece15.o-ring circle(big) 16.o-ring circle(small)17.switch 18.hose band19.air hose 20.sub-tie-in21.over ...