diamond drill,diamond core drills,diamond core bits: 1,over 20years experience 2,many kinds of size 3,super quality ISO9001:2000,SGS certification.(over 20years experience. one of the leader in China.) diamond drill,diamond core drills,diamond core bits Electroplated diamond core drill bit for mine, coal mine drill bits. all kinds of drill bit. the size is following:1, Double tube drill:Φ28,Φ36,Φ ...
