WIRE - #4 ALUM U.S.E. SINGLE STRAND, LF | Southwire Type RHH or RHW-2 or USE-2 conductors are used with conduit as specified in the National Electrical Code. When used as Type USE-2, conductors are suitable for use as underground service entrance conductors for direct burial at conductor temperatures not to exceed 90°C. When used as RHW-2 or USE-2, conductor temperatures shall not exceed 90°C in wet or dry locations. Voltage rating for RHW-2 or RHH or USE-2 conductors is 600 volts.