328B Features: -Air Geared Orbital Sander.-Dual action pad motion (5/32" orbit).-A long-life, low vibration performance.-Air Inlet: 1/4".-Performance Rating: Heavy Duty.-@ Load: 16 cfm.-Min. Hose Size: 3/8".-Pad Diameter: 8".-Vacuum Ready: No.-Free Speed: 900 rpm.-Average Air Consumption: 4 cfm. Construction: -Balanced ball bearing construction. Specifications: -Sound (Pressure/Power): 90.45/93.7 dBA.-Rated Power: 0.25 hp. Dimensions: -Weight: 4.7 lbs.