Power tongs are mechanical wrenches used on the floor of a drilling rig to make up and break out joints of drillpipe, casing, and tubing as it grips the tubular. It is either air or hydraulic powered with a throttle handle. Most power tongs require backup although some have their own backup. Some power tongs also have an automatic torque adjustment. These are reversible and have two speeds. High speed is used for making up and low speeds for breaking out.