Body contact pad - You hold onto the solid stainless steel pad (no aluminum foil used). The other end is inserted into the wand. Used to turn your body into a conductor when using the Violet Wand. Note the spark gap isolator plug. This insulates you from line voltage in case of wand malfunction. Also note that bead chain is used instead of wire. This is an important safety feature. Do not substitute wire for the bead chain. The 7/16 inch (11mm) diameter should fit most wand sockets.