Lightweight design for small workspace. Chromium plated surface of piston, prolonging the service life of piston. Plunger has the function to retracting automatically. The joint of this product is a ZG-3/8 19 tooth British taper thread. In order to operate correctly, all oil cylinders need to be connected with solid and flat surfaces.For example, using thin oil cylinders in sandy soil or loose surfaces will cause damage to the oil cylinders. Due to the different display and different light, the picture may not reflect the actual color of the item.