... . Recommended Bit type: 437, Drilling weight: 0.35~0.90 KN/mm, Rotary speed, 240~60 r/m.2, Soft with ... . Recommended Bit type: 517, Drilling weight:0.35~1.05 KN/mm, Rotary speed, 220~60 r/m.3, Medium soft ... . Recommended Bit type: 537, Drilling weight 0.35~1.05 KN/mm, Rotary speed, 200~40 r/m. F/FC series ...