TH122 DTH hammer:Valveless DTH hammer Material:Carbide Certificate: ISO9001:2008,SONCAP High impact power with low frequency Usage: Drill holes from 135mm to 185mm."Matched products: 76mm drill rods with API 2 3/8"REG BOX bits with COP54.DHD350,Mission50,QL50,SD5,XL5 shanksApplication fields: all kinds of fields, such as mining, quarry, tunnel, bridge, construction and etc., but extremely ...