Standard Drill Size Codes and Diameters
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Standard Drill Size Codes
Diameter	Size Code
.0135	80
.0145	79
.0156	1/64
.0160	78
.0180	77
.0200	76
.0210	75
.0225	74
.0240	73
.0250	72
.0260	71
.0280	70
.0292	69
.0310	68
.0312	1/32
.0320	67
.0330	66
.0350	65
.0360	64
.0370	63
.0380	62
.0390	61
.0400	60
.0410	59
.0420	58
.0430	57
.0465	56
.0469	3/64
.0520