The main characteristics: High speed-regulating precision, largespeed-changing range (The speed ratio ranges from 200 to 1000 freely). Contimuous in running, smooth in driving, stable in performance and low in noise, this is reliable and infinitive flow adjustment. Bus it changes the speed by manual adjustment, low degree of automation, and speed-regulation should be effected in running. Do not turn the hand wheel of speed-regulation when the machine stop. The stepless speed reducer is not used in such an occasion where overload or running-blockage is easy to occur.