The Silent Green Pneumatic Water Fed Grinder/Polisher is an excellent high quality/low cost air powered machine for your grinding and polishing needs. Low speed at high torque makes this an amazing tool for polishing. It's small design allows for a light weight handling with variable speed adjustment in the handle. Comes with an in-line oiler and five larger rotor blades for maximum efficiency. Does not include backer pads. Excellent for use with 4", or 5" 3M Hook and Loop disks