1. Drill holes of various sizes without changing drill bits. 2. The hole is smoother and rounder. 3. Compared with traditional drill bits, the impact is minimal and it is almost impossible to break. 4. Prevent metal shavings from flying and improve safety. 5. Suitable for steel plate, aluminum plate, wood plate, plastic plate, etc. notes: 1. Not compatible with impact drills. 2. Do not set the drilling speed too high, so as not to damage the . 3. It is recommended to oil the drill bit before each use. 4. Please drill smaller holes for smoother drilling. 5. The sheet metal to be drilled should not be thicker than 0.38 inches. Colour:gold Material:high speed steel Package Contents: 5 x step drills 1 x step drill bit Only the above package content, other products are not included. Note: Light reflection 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.