Insert Bit Sizing by Head Type

Phillips

Philllips Point #	Sheet Metal Screws	Wood Screws		Machine Screws
Philllips Point #	Flat, Round, Oval Stove Binding	Flat, Oval	Round	Flat, Oval Binding	Round, Fillister	Truss, Brazier Button
0	0, 1	0, 1	0, 1	0, 1	0, 1	0, 1
1	2, 3, 4	2, 3, 4	2, 3, 4	2, 3, 4	2, 3, 4	2, 3, 4, 5
2	5, 6, 7, 8, 10	5, 6, 7, 8, 9	5, 6, 7, 8, 9, 10	5, 6, 8, 10	5, 6, 8, 10	6, 8, 10
3	12, 14	10, 12, 14, 16	12, 14, 16	12, 1/4"	12, 1/4", 5/16"	12, 1/4"

Slotted

Slotted Point #	Screw Size	Slot Screw Width		Thread Dia.	Maximum Head Diameter
Slotted Point #	Screw Size	Min	Max	Thread Dia.	Flat or Oval Head	Round Head	Fillister Head	Binding Head	Pan Head	Truss Head
4-5	3	.027	.035	.099	.199	.187	.161	.208	.193	.226
4-5	4	.031	.039	.112	.225	.211	.183	.235	.219	.257
6-8	5	.035	.043	.125	.252	.236	.205	.263	.245	.289
8-10	6	.039	.048	.138	.279	.260	.226	.290	.270	.321
10-12	8	.045	.054	.164	.332	.309	.270	.344	.322	.384

Square

Slotted Point #	Tapping Crews	Wood Screws	Machine Screws
0	3, 4	3, 4	3, 4
1	5, 6, 7	5, 6, 7	5, 6
2	8, 10	8, 9, 10	8, 10
3	12, 14	12, 14	12, 14

6-Lobe / Star / Torx®

Screw Size	Thread Dia.	Internal Torx Washer Head	Pan Head	Flat Head	Hex Head	Truss Head	Fillister Head	Oval Head	Socket Head Cap	Socket Set Screw
2	.086	T7	T7	T6	----	----	----	----	----	----
3	.099	T8	T8	T7	----	----	----	----	----	----
4	.112	T9	T9	T8	T9	----	T9	----	T10	T6
5	.125	T10	T10	T9	T10	----	T10	T10	T10	T7
6	.138	T15	T15	T10	T15	T10	T15	T15	T15	T7
8	.164	T20	T20	T15	T20	T15	T20	T20	T25	T8
10	.190	T25	T25	T20	T25	T20	T25	T25	T27	T10
12	.216	T27	T27	T25	T27	T25	T27	T27	T27	T10
1/4"	.250	T30	T30	T27	T30	T27	T30	T30	T30	T20
5/16"	.312	----	----	T40	T40	T40	T340	T40	T45	T27
3/8"	.375	----	T45	T40	T45	T45	T45	T45	T50	T30
7/16"	.437	----	T50	T50	----	T45	T50	T50	T55	T40
1/2"	.500	----	T55	T50	----	T50	T55	T50	T55	T45