You can pump out the push rod using the black lever or pull it out by hand (similar to the principle of a silicone gun). With the black feed lever, you can apply pressure to the clamp. Over 100 kg is possible. This ensures everything is tightly pressed or spread apart. Ideal for installing door frames in masonry, providing break-in resistance with a tilted window, securing items in the trunk, or serving as a mobile coat rack in the hallway or door frame.