For adapting schedule 40 non-metallic conduit to threaded accessory boxes on metallic systems Non-conductive safe will not rust or corrode Attaches conduit to outlet or junction box Features. Size 3. Threaded fittings. Attaches conduit to outlet or junction box. Non-conductive safe will not rust or corrode. Male threads on one end and socket on the other. For adapting schedule 40 non-metallic conduit to threaded accessory boxes on metallic systems. UL Listed Specifications. Dimensions: 4 inches high x 4 inches wide x 31 inches long. Weight: .04 lbs.