1.High strength due to whole body casting with high quality material.  2.Smooth running, high working pressure and low noise with 2-step to 4-step helical gear mechanism.  3.Single plate electromagnetic clutch is sensitive and reliable.  4.Operational altitude is reasonably arranged, moving-bed opens to its maximum.  5.Electrical system is designed in conformity with IEC standard.  6.Single, continuous operation and opening delay are available, delay range adjustable.  7.Reliable safety system.