DC motors models RS-550 or RS-555, Carbon brush dc motor, Cylinder, Diameter35.5 mm, length 57 mm; shaft 3.175 mm, fixing screw 2-M3.0 mm. Operating voltage: 3.6~60V, At no load Speed 3,000~25,000 r.p.m, Output about 3~90 W. fit for power tools, massager, paper Shredder, vacuum cleaner, printer, air pump, vending machine, blender, , drill & screw driver, forest tools, etc.