Description： Adjustable screw rod to adjust to suitable operating height. Piston rod and oil cylinder are rising and lowering in linear movement. Conscientiously fix the oil cylinder sheathing pump body to the bottom to keep from oil-leaking while in operation. Top with cross grooves (loading contact segment). Pressing handle to press up and down to make the piston rod rise. The release valve is to control raising or lowering function. Capacity: 6 Ton (12000lbs) Lifting Range: 7-1/2″ to 12-3/4″ plus screw rod 2-1/2″ max 15-1/4″ Min. Height: 7-1/2″ Max. Height: 12-3/4″ Plus Adjustable Screw Rod 2-1/2″ .