... bearingaircooled bearing typeFormation or layer soft ,medium soft ,hard,medium hard,very hard formationButton size (extra features)Button bit,saw teeth1) ... K- wide teeth4)G- Gague protectionMaterialAlloy steel ,carbidePackingWooden case or steel casePayment termsT/T,L/C,Western unionDelivery termsBy ... 8-9 1/2539-83360-40hardSandy, Shale, Quartzite, Hard Dolomite, Hard Sandstone etc.695.~-174.63 3/4-6 7 ...