When designing special rotation and rugged construction, welded moving parts supported by bearings, main frame is made, the composition of the assembly unit, when the no-load and load, a lateral tooth surface is not smooth drive shaft driven control arm, can not go Movement inside out, using a crank handle, the arm can be pulled out to 100%, for the use of a crane loading. Benefit point: long cargo indoor crane lifting operation single operation to store up to 70 meters and longer shelf low level suitable for large-capacity storage to save space, it does not require a dedicated channel, and industrial forklift trucks