Material: High Speed Steel. Shank Type: Reduced. Drill Bit Diameter: 7/16 in. Application: For Wallboard and Plywood, Plastic, Wood. Size: 7/16 in. Shank Diameter: 1/4 in. Number of Pieces: 1. Diameter: 7/16 in. in. Usage: HSS Drill Bit. Product Name: Drill Bit.