The Klein Tools 66090 6-Piece Impact Socket Set consists of the most commonly used impact socket sizes used in utility and construction work. This set includes two 3-in-1 sockets with an alignment slot to tighten and loosen most pole hardware. Each impact socket features two coaxial spring-loaded sockets in one. The high-torque, 12-Point design is easier to position on fasteners including square fasteners. Bundled in a convenient carrying case. With a cross hole design, this unit can help maintain socket connection to the adapter or impact wrench.