The MADI SS-5 Concentric Neutral Wire Twister with Penta Socket combines two essential underground functions in one durable tool. Designed for single- and three-phase conductors, the twister accommodates up to a single alt 1/0 copper concentric, while the 13/16-inch penta socket is ideal for opening transformers. A half-inch drive shank with flats allows use with drills, and forged CrMo steel provides the strength and durability needed for everyday utility work. www.madilinemantools.com/products/concentric-neutral-wire-twister-with-penta-socket