They are used for drilling all kinds of stones,glass,ceramics,refractory materials and reinforced concrete and so on stone drills1, Used for : all kinds of stones , such as granite ,marble ,glass,etc .2,Size: 8mm--200mm.M14,5/8"-11 Connection3,Feture:fast cutting and long life4,MOQ:50pcs5,Payment : T/T6,Packing : Carton7,Delivery time : Normally 20 days8,Delivery port: Xiamen Various ...