Our SPT1 Extension Wire (Zip Cord) is perfect for making your own custom extension cords. Use with male plugs and female sockets to make your own extension cords or make extensions from string to string or string to power source. The wire also works great for connecting power sources, such as, from tree to tree or string to string. 100′ Length-NOT ON A SPOOL. 250′ Spool, 500′ Spool. 8 AMP/986 Watt Max.