Wire & Cable Your Way offers URD wire at the best prices you'll find anywhere – available by the foot with no cut charges. This underground electrical wire may be used for underground secondary distribution and service entrance applications at 600 volts or less. They may be either directly buried or installed in ducts (lower allowable ampacity), in either wet or dry locations. Underground Secondary Distribution Cables are especially suited for applications requiring superior resistance to abrasion, scoring and crushing. Ampacities are for non code complying installations. For installations covered by National Electrical Code (NEC), see the appropriate section of the NEC. Ampacity based on earth thermal resistivity of 90°cm/watt, 90°C conductor temp, 20°C earth ambient temperature. 100% load factor and 36” depth of burial. Values based on no current in the neutral conductor.