This 250-foot spool of SPT-1 Lamp wire is rated for up to 300 volts. UL Listed.
This wire is 18/2 which means that the copper wires inside the cord are 18 Gauge and there are 2 parallel wires. The SPT-1 is the measurement of the insulation thickness of the cord. The Insulation thickness provides varying degrees of resistance to heat and abrasion.
• SPT-1 This wire is U.L. Listed for use in hanging fixtures & sconces, easily slips 1/8 IP (3/8” dia.) pipe.
• SPT-1 1/2 This wire is U.L. Listed for use in fixtures hanging by a chain, easily slips 1/8 IP (3/8” dia.) pipe.
•SPT-2 This wire is U.L. Listed for use in portable table and floor lamps, difficult to slip 1/8 IP (3/8” dia.) pipe.
Unfortunately, the thicker the lamp cord, the more problems you may encounter when trying to insert, pull or slip the cord through your lamp or fixture.