1,bit API& ISO 2,bit size 8 1/2 215.9mm 3,bit iadc code 517 4,bit rubber/journal ... ”),200.0mm(7 7/8”)212.7mm(8 3/8”),215.9mm(8 1/2”),222.2mm8 3/4”) 241.3 ... ,124,126,127,136,137 211,311216,217, 227TCI(IADC)415,435, 417,437515,525,535,545, 517,527,537,547615 ... the layer.4)plz tell the quantity. 8 1/2 215.9mm iadc 517 tricone drill bit