and high quality Precision grinding, suitable for mass use and easy to re-grind, they can easily enlarge existing holes and can pierce any arc. The carbide cutter head is specially designed to pass through holes clearly in the final texture and thin material, which is very suitable for embroidering hidden hinges and door clocks. It is and more accurate to use this drill in a drill press. Suitable for: wooden doors Hole drill diameter: 15-50mm Material:Hard alloy colour:Blue + Silver Package Contents: 1 x 15mm Forstner Drill Bit 1 x 16mm Forstner Drill Bit 1 x 18mm Forstner Drill Bit 1 x 20mm Forstner Drill Bit 1 x 22mm Forstner Drill Bit 1 x 25mm Forstner Drill Bit 1 x 30mm Forstner Drill Bit 1 x 32mm Forstner Drill Bit 1 x 35mm Forstner Drill Bit 1 x 50mm Forstner Drill Bit Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.