Cutting chisel edge with high centring accuracy due to strong core and special point geometry. High roundness and alignment accuracy of the deep hole- thanks to 4 guide chamfers. Outstanding chip evacuation due to 4 internal cooling channels from dia 3.8 mm. Up to 3.7 mm dia with 2 internal cooling channels. Straight major cutting edges with honed edges and special flute profile for short chips- even on long chipping materials. Note: Flute length LC = L2 + 1.5 x DC. For process reliability when using the 12xD drill- an initial center drilling with NC spotting drills No. 121068- 121130 is necessary. Standard: Manufacturer’s standard Tolerance nominal dia : m6 Number of cutting edges Z: 2 Tolerance nominal dia : m6 recommended maximum drilling depth L2: 138.8 mm Overall length L: 204 mm Shank dia Ds: 12 mm Feed f in stainless steel > 900N/mm2: 0.15 mm/rev.