... -hard drilling information 6) Bit size:8 1/2"IADC code:5372,products details 3,Packingor steel box4,we can ... 131117,124,126,127,136,137 211,311216,217, 227TCI(IADC)415,435, 417,437515,525,535,545, 517,527 ... ,537,547615,625,635,,617,627,637,737512,522,532,612,622,632,7326,Payment termsT/T ... inquiry1)the size of the tricone bit.2)the IADC tooth model,like 537G3)plz tell the drilling information ...