Sometimes you need the extra strength of an impact-rated tool on stubborn fasteners. The Powerbuilt 3/8 Inch Drive 7/8 Inch Impact Socket is the perfect solution. Each socket is made from Chrome Vanadium steel for added durability. Impact sockets feature an industrial-grade Black Phosphate finish that prevents corrosion and extends the life of the tool. The impact socket also features 6 point broaching for maximum grip on fasteners. Powerbuilt impact sockets provide increased strength and durability over and above the competition. Powerbuilt impact sockets exceed ANSI standards and are strength tested for performance and quality.