By virtue of the inserts being triangular, the curved corners on the cutting edges of the two inserts may be positioned relatively close together and yet sufficient space is left between the inserts to enable the drill shank between the inserts to be relatively thick and strong even at {HEAD ~ increased length} to {TAIL ~ diameter} ratios 
By virtue of the inserts being triangular , the curved corners on the cutting edges of the two inserts may be positioned relatively close together and yet sufficient space is left between the inserts to enable the drill shank between the inserts to be relatively thick and strong even at { HEAD ~ increased length } to { TAIL ~ diameter } ratios
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