NATIONAL Wire&Cable - 18 Gauge 2 Conductors Premium Electrical Wire - Made in USA - 18 AWG Wire Stranded PVC Cord Copper Cable 25 Ft. Flexible Low Voltage LED Cable Lamps Lighting Automotive - Amazon.com
Cambridge 40 ft. 18 AWG Red Wire at Tractor Supply Co.
ANCOR 18 AWG Primary Wire by the Foot | West Marine