... qualith DTH drill bit, DTH air hammer. Now we can supply 90mm-254mm(3.5"-10") DTH air hammer bit, 340 ... ,380, COP44, COP54, COP64, COP84 , 3"-8" DTH air hammer and 340,350,360,380 4",5",6",8" quick hammer ... with very good price and service. No.ModelOutside diameterLength (without bit)Weight (without bit)Working ... (at 1.7Mpa)15-34API(4 1/2)" REG195-254 newly designed air hammer