Bosch Brocas escalonadas 4-12, 4, 6, 66.5

The HSS Step Drill Bit performs smooth, burr-free drilling in several diameters with one drill bit. It is ideal for deburring, for drilling round holes and for enlarging existing ones. Pre-punching is not necessary, because the split-point tip allows for an easy start. Its CNC ground spiral flute enables optimised chip removal and less vibration for even drilling. The highest cutting performance and absolute smoothness are guaranteed due to axial and radial relief grinding. This step drill bit is suitable for use on thin materials, such as non-ferrous metals, sheet plastic, sheet steel, plastic and stainless steel. The step drill bit is made of HSS (high-speed steel) and coated with AlTiN (Aluminium Titan Nitride). It thus offers the maximum lifetime possible and does not require the use of a coolant. Easily visible and durable markings of the hole diameter are provided by laser-marked figures in both spiral flutes. In addition, the 3-flat shank prevents slipping in the chuck and also provides powerful high-torque transmission.