GT60 102mm Dome Retrac Drill Bit The GT60 102mm Dome Retrac Drill Bit is a high-performance threaded retrac button bit engineered for demanding rock drilling applications in mining, quarrying, construction and tunneling. Featuring a 102 mm drilling diameter with a φ14×8 + φ13×6 dome button configuration, this bit delivers a balanced combination of drilling efficiency, wear resistance and hole stability. The dome-shaped tungsten carbide buttons maintain effective contact with