... 17 1/2" 2.high quality,best price 4.number of blade :4,5,6,7,8,9,... 1,Application: ... protection and low torque design improve rate of penetration .4,CFD hydraulic balance design results in better bit cleaning ... -pipes75/54.5 94/68PDC center drill bitConcave 3 wing bit60 75 94 113 1331-18Arc pillar60 75 94 ... usually from China to European about 25 days. To West of American 20 days.3.Can I expect a quality ...