A screw jack consists of a heavy-duty vertical screw with a load table mounted on its top, which screws into a threaded hole in a stationary support frame with a wide base resting on the ground. When the handle is turned clockwise, the screw moves further out of the base, lifting the load resting on the load table.
Thread screw jacks are the accessory used to safely adjust the scaffold legs. This may be necessary when different working heights are encountered or when the scaffold is mounted on sloped surfaces.
For many types of scaffolding system, such as ringlock system, frame system and cuplock system.
