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. Attention: Sizes ending with X = cutter dia tolerance h7. Note: Flute length LC = L2 + 1.5 x DC. Standard: DIN 6537 Tolerance nominal dia : m6 Number of cutting edges Z: 2 Tolerance nominal dia : m6 recommended maximum drilling depth L2: 72.5 mm Overall length L: 153 mm Shank dia Ds: 20 mm Feed f in stainless steel > 900N/mm2: 0.25 mm/rev.