Very powerful package, spark voltage is in excess of 45,000 volts measured over the entire rpm range, and spark energy is as impressive. Despite their size of just 3 1/2"x1 1/2"x2 3/4" (85mmx40mmx60mm), the energy storage capability and power reserves are very high. The 3 Ohm coils are compatible with Single Fire ignitions such as Twin Tec's 1005 & 1007 series, S&S Hi-4 and Dyna 2000 series. Features a wire set, which is pre-terminated with both 90° and 110° spark plug boots. Wires are 23 1/2" (600mm) and 17" (430mm) long. Comes with an extra set of 90° plug boots with connectors and detailed instructions.