Step drill bit Ø 11.00 / 8.50 mm HSSCo Profi

Right-hand step drill with a straight shank. Made from cobalt high-speed steel (HSSCo). For drilling tap holes with a 90° countersink in carbon, structural and alloy steels and cast iron.
Profi drills centre easily, usually without centre-punching. They last longer and can drill holes up to five times faster.
The special split point helps the drill centre itself and resist wandering. A centre-punch mark is rarely needed. 
Profi drills bite readily and produce more accurate holes. They can last up to three times as long and reduce drilling time for the home user by a factor of up to five. These drills receive an additional protective treatment to improve corrosion resistance.

d_1- 11.0 mm_; d_2- 8.5 mm_; l_1- 25.5 mm_; l- 94 mm_; L- 142 mm