No need to order special collets.7 with 3 teeth- dia size 1.8 even number of teeth and irregular spacing. For highest concentricity and process reliability.
Material: Chrome molybdenum steel- surface burnished.Sturdy shape especially for use with electric or compressed air impact wrenches. With cross hole and snap ring groove for securing sockets. Impact Socket, 3/8 inch Drive, 6 pt, Deep, 1/4 inch Square drive: 3/8 in dia drive output end: 19 mm Length: 63 mm.