Carbon brush dc motor Diameter 35.5mm,Length 50mm,Shaft 3.175mm Voltage: 3.6~36V No load Speed 2000~25000r.p.m Output:5~75W DC motors models RS-540 or RS-545, Carbon brush dc motor, Cylinder, Diameter35.5 mm, length 50 mm; shaft 3.175 mm, fixing screw 2-M3.0 mm. Operating voltage: 3.6~60V, At no load Speed 2,000~25,000 r.p.m, Output about 3~75W. fit for power tools, massager, hair dryer, paper ...