... of stones,glass,ceramics,refractory materials and reinforced concrete and so on Sintered Diamond Core Drill Bits are used for drilling ... all kinds of stones,glass,ceramics,refractory materials and reinforced concrete and ... 8mm--200mm.M14,5/8"-11 Connection3,Feture:fast cutting and long life4,MOQ:50pcs5,Payment : T/T6,Packing : Carton7 ...