The body column is made of C-shaped steel, and the cylinder piston is standardly equipped with a 30MM hard chrome solid rod for one ton. The whole vehicle is a high-quality oil seal to eradicate the criticism of oil leakage.

Hydraulic rises and falls, and the speed is stable; the speed is controllable, and the pulley transmission is used between the door frames, so that the door frame rises without swinging and very smoothly.

The valve spool adopts a split, which is different from the whole p