T45 89mm Flat Face Standard Body Domed Button Bit The T45 89mm Flat Face Standard Body Domed Button Bit is a top hammer threaded rock drilling bit designed for efficient and stable drilling in mining, quarrying, tunneling, construction and rock excavation applications. It features a T45 threaded connection, 89 mm drilling diameter, flat face design, standard body and domed tungsten carbide buttons. The domed button profile provides a balanced combination of rock penetration,