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.