Valianto SD-3091AD 5-Inch Air Dual Action Vacuum Green Aluminum Sander Update version to 3091 with dust-collecting design High free speed of 11000 rpm shorten your working time improve efficiency Pad polishing way maximize the polishing effect more uniform and smoother Apply to polishing and shaving jobs on material like wood,metal,stone,etc Compact ergonomic design highly reduce operators' fatigue while delivering the best performance