1-inch long black impact socket, 21 mm square, model 88305M21, designed for use with pneumatic wrenches and impact tools in heavy-duty applications. It features an extra length to help reach deep and difficult areas, and is made of hardened steel to withstand high torque and impacts. The black coating is rust and corrosion resistant, while the square design provides strong and secure fastening when loosening and tightening nuts in automotive workshops and industrial equipment.