Galvanized steel enclosure. Single phase, 3-wire, four jaw, 600 V maximum. Jaws fabricated from high conductivity, tin-plated, copper alloy. Insulating jaw support blocks of high impact, non-tracking thermoset polyester. Safety guides reduce chances of accidental contact and aligns meter in sock. Uses RX style hub (not included). Includes two ground lugs. Swing switches are stainless steel. Provision for 5th jaw. UL listed.