This Tesla Coil secondary has 600 turns of 24awg magnet wire. The secondary coil is 3.5" in diameter and 17" long, 16" of which has magnet wire wound onto it. The length of the wire is approximately 550 feet long. The Tesla Coil comes with 2 end caps made out of HDPE (high density poly ethene), they are a very tight fit. There is also a center hole for attaching a Tesla Coil top capacitor.