Mechanical Jacks usually use mechanical advantage to allow a human to lift a vehicle by manual force alone. When the upper cap nut is rotated anti-clockwise the screw (threaded RAM) starts lifting upwards moving the object to certain height and its clockwise function brings the object down to its actual position. Mechanical Jack is also used as a supporting jack with hydraulic jack. For the longer life of mechanical jack a hole is provided in the nut cap which is used to provide grease to the bearing fitted in the nut cap so that the jack.