1,controlled by double motors, one motor control driving,another one control tightening, more power of

     tighten.and to reduce machine wearing, can be used 3 times longer than other machine.

2,the machine is controlled by 3 voltage transformer,from 220V input transfer to 110V output, all voltage are    

     100V, more safe and steady.

3,all functions are controlled by IC digital frequency conversion processor,make the machine more  intelligent,more  efficient.