VEVOR Hydraulic Shop Press, 20 T H-Frame Pneumatic Shop Press with Press Plate, Stable Garage Floor Adjustable Hydraulic Press with Triangular Support, Fit for Bending, Straightening & Stamping

The tension spring inside the hydraulic cylinder generates a pulling force that pulls the piston rod back. Thank you! If this answer does not resolve your current issue, please contact us again for assistance.