Durable to keep new shine for a long time.Feature:1. This is a type HSS steel large step cone drill cobalt bit fixed hole milling cutter.2. It is made of high-quality HSS steel and is plated with titanium to reduce friction and heat.3. Very suitable for cutting holes in various materials, including steel, brass, wood, plastic, etc.specification:Type: core bitMaterail: HSS high-speed steelCoating: CobaltDimensions x total length x shank diameter x shank length3 / 16-1 / 2 x about 57mm x about 6mm x about 24mm1/8-1/2 x about 77mm x about 6mm x about 24mm1/4-3/4 x approximately 73mm x approximately 9mm x approximately 24mm3/16-7/8 x approximately 77mm x approximately 9mm x approximately 24mm1 / 4- 1-3 / 8 x about 76mm x about 9mm x about 24mmDimensions include:3/16-1/2: 3/16'', 1/4'', 5/16'', 3/8'', 7/16'', 1/2''1/8-1/2: 1/8'', 5/32'', 3/16'', 7/32'', 1/4'', 9/32'', 5/16'', 11/32'', 3/8'', 13/32'', 7/16'', 15/32'', 1/2''1/4-3/4: 1/4'', 5/16'', 3/8'', 7/16'', 1/2'', 9/16'', 5/8'', 11/16 inches, 3/4 inches3/16-7/8: 3/16'', 1/4'', 5/16'', 3/8'', 7/16'', 1/2'', 9/16'', 5/8 ", 11/16 ", 3/4 ", 13/16 ", 7/8 "1/4-1-3/8: 1/4'', 3/8'', 1/2'', 5/8'', 3/4'', 7/8'', 1'', 1-1/8 ", 1-1/4 ", 1-3/8 "
