Coleman Cable 54703 250-Feet Solid Underground Sprinkler System Wire, 18 Gauge 3 Conductors Irrigation Cable, 18/3 This wire is designed to be used as underground sprinkler system wire. Its made with hard insulation to withstand the toughness of nature. This cable consists of two bare copper insulated conductors with an overall jacket.The wires are 18 GaugeThree conductorsConductors are SolidApproved by the Underground Golf Course Sprinkler System Cable Laboratory