#66 drill bit size

#66 drill = .0330 in = 0.84 mm. Closest metric drill: 1 mm.

Nearby drill sizes

Drill	Type	Inch	mm	Difference
#69	number	.0292 in	0.742	-3.8 thou
#68	number	.0310 in	0.787	-2.0 thou
1/32	fraction	.0313 in	0.794	-1.8 thou
#67	number	.0320 in	0.813	-1.0 thou
#66	number	.0330 in	0.838	0.0 thou
#65	number	.0350 in	0.889	2.0 thou
#64	number	.0360 in	0.914	3.0 thou
#63	number	.0370 in	0.940	4.0 thou
#62	number	.0380 in	0.965	5.0 thou

1 thou = 0.001 in = 0.0254 mm. Drills a few thou apart are usually interchangeable for clearance holes, but not for tap drills or reamer pilots.