Pneumatic drill hammers are ideal for fast drilling of hard stone formations, due to the high frequency of tips hitting the rock. When using a DTH drilling hammer, a drill bit is put in motion by air pressure, and hits the rock with pre-determined strength, which crushes the rock layer, with resulting fragments consequently removed by air pressure. AGIVA Int’l carries high-quality DTH drill bits, as well as impact heads. Beside conventional drill heads AGIVA Int’l also distributes hammer drill heads used for driving the casing in a concentric system. lubricant.