Model specification: DHD3.5, DHD340,DHD350,DHD360,DHD380,DHD112, (7) Specification of dth hammer button bits:Diameter: (mm)1-2 inch low air pressure DTH Shank: BR1, BR2, DHD2.5 57/64/70/76/80/82/90mm (8) 3 inch high Air pressure DHT Shank: BR3,DHD3.5,COP34,COP32,QL30,M30,IR3.5 85 / 90 / 95 / 100 / 105/110mm (9) 4 inch high Air pressure DHT Shank:DHD340,COP44,M40,SD4,QL40 105 / 110 / 115 / 120 / 127/130mm (10) 5 inch high Air pressure DHT Shank:DHD350,COP54,M50,SD5,QL50 133 / 140 / 146 / 152 / 165mm (11) 6 inch high Air pressure DHT Shank:DHD360,M60,SD6,QL60,COP64 152 / 165 / 178 / 190 / 203mm (12) 8 inch high Air pressure DHT Shank:DHD380,COP84,M80,SD8,QL80 195 / 203 / 216 / 254 / 305mm (13) 10 inch high Air pressure DTH Shank:SD10, NUMA100 254/270/279/295/305mm (14) 12 inch high Air pressure DTH Shank:SD12,DHD1120,NUMA120,NUMA125 305/330/343/356/368/381mm (15) 15 inch high Air pressure DTH bits Shank: DHD1150, SD15,NUMA125 381/391/435/457/483/503mm (16) Over 20 inch high Air Pressure DTH bits Shank: NUMA180,NUMA240,483/508/560/578/610/660mm Top sub connection: API 2 3/8" Reg Chuck connection configuration: IR3.5 Available bit size/mm: 90-115 Length(without bit)/mm: 888 Outside diameter/mm: 82 Net weight(without bit)/kg: 25 Impact rate : At 1.5Mpa,25HZ Recommended rotation speed: 25-40r/min Air consumption, CFM& (M3/min) Work Pressure 1MPa 3.8m3/min 1.5MPa 7.5m3/min 1.8MPa 2.4MPa.