The Master Lock No. 487 Rotating Electrical Plug Lockout Device accepts cords with up to 3/4in (19mm) diameter and an electrical plug up to 2-1/4in (57mm) diameter x 3-1/4in (82mm). Device surrounds the electrical plug and protect against accidental reconnection. The unique, patented rotating design allows for easier installation in confined space applications. The tough, lightweight Zenex™Thermoplastic body withstands chemicals and performs effectively in extreme conditions. Includes high-visibility permanent safety labels. For 120 volt plugs and many 240 volt plugs.