CIR90A 95mm DTH Drill Bit - Drop Center Face Ballistic Button Rock Drill Bit The CIR90A 95mm DTH drill bit is a rock drilling bit designed for down-the-hole drilling applications. It features a 95mm drilling diameter, drop center face design and ballistic carbide buttons for efficient rock penetration and impact transfer. This CIR90A DTH button bit is equipped with a 6 × 14mm + 5 × 13mm carbide button configuration and 3 water holes for effective flushing during drilling. The