KATO Fastening Systems, Inc.

Insert Dimensions

KATO Insert Dimensions and Specifications

Please select the thread type below, or you can scroll through the list:

Unified Coarse
Unified Fine
Metric Coarse
Metric Fine

Nominal Thread Size	Nominal Length*					Free Outside Diameter		Number of Free Coils**
	Length of Insert (in Diameter)					Free Outside Diameter		Nominal Length (Diameter)
	1	1 1/2	2	2 1/2	3	Min	Max	1	1 1/2	2	2 1/2	3
	Unified Coarse
2-56	0.086	0.013	0.172	0.215	0.258	0.110	0.119	3	5-1/4	7-3/8	9-5/8	11-7/8
3-48	0.099	0.148	0.198	0.248	0.297	0.128	0.139	2-7/8	5	7-1/4	9-3/8	11-1/2
4-40	0.112	0.168	0.224	0.280	0.336	0.144	0.159	2-3/4	4-3/4	6-3/4	8-7/8	10-7/8
5-40	0.125	0.188	0.250	0.312	0.375	0.158	0.173	3-1/4	5-1/2	7-3/4	10	12-1/4
6-32	0.138	0.207	0.276	0.345	0.414	0.178	0.193	2-3/4	4-3/4	6-7/8	8-7/8	10-7/8
8-32	0.164	0.246	0.328	0.410	0.492	0.205	0.220	3-1/2	6	8-3/8	10-3/4	13-1/4
10-24	0.190	0.285	0.380	0.475	0.570	0.244	0.259	2-7/8	5	7-1/8	9-1/4	11-3/8
12-24	0.216	0.324	0.432	0.540	0.648	0.270	0.285	3-1/2	6	8-3/8	10-5/8	13-1/8
1/4-20	0.250	0.375	0.500	0.625	0.750	0.310	0.330	3-3/8	5-3/4	8	10-3/8	12-3/4
5/16-18	0.312	0.469	0.625	0.781	0.938	0.380	0.400	4	6-5/8	9-1/4	11-7/8	14-5/8
3/8-16	0.375	0.562	0.750	0.938	1.125	0.452	0.472	4-3/8	7-1/4	10	12-7/8	15-3/4
7/16-14	0.438	0.656	0.875	1.094	1.312	0.526	0.551	4-1/2	7-3/8	10-1/4	13-1/8	16-1/8
1/2-13	0.500	0.750	1.000	1.250	1.500	0.597	0.622	4-7/8	7-7/8	11	14-1/8	17-1/8
9/16-12	0.562	0.844	1.125	1.406	1.688	0.669	0.694	5-1/8	8-1/4	11-1/2	14-3/4	17-7/8
5/8-11	0.625	0.938	1.250	1.562	1.875	0.742	0.767	5-1/4	8-1/2	11-3/4	15	18-3/8
3/4-10	0.750	1.125	1.500	1.875	2.250	0.881	0.906	5-7/8	9-3/8	13	16-1/2	20-1/8
7/8-9	0.875	1.312	1.750	2.188	2.625	1.022	1.052	6-1/4	10	13-3/4	17-1/2	21-1/4
1-8	1.000	1.500	2.000	2.500	3.000	1.166	1.196	6-3/8	10-1/8	14	17-3/4	21-5/8
1 1/8-7	1.125	1.688	2.250	2.812	3.375	1.315	1.355	6-1/8	9-7/8	13-5/8	17-1/2	21-1/4
1 1/4-7	1.250	1.875	2.500	3.125	3.750	1.443	1.483	7	11-1/4	15-3/8	19-1/2	23-3/4
1 3/8-6	1.375	2.062	2.750	3.438	4.125	1.598	1.643	6-1/2	10-1/2	14-3/8	18-3/8	22-1/4
1 1/2-6	1.500	2.250	3.000	3.750	4.500	1.727	1.772	7-1/4	11-1/2	15-7/8	20-1/8	24-1/2
Unified Fine
3-56	0.099	0.148	0.198	0.248	0.297	0.131	0.146	3-3/8	5-5/8	8	10-3/8	12-5/8
4-48	0.112	0.168	0.224	0.280	0.336	0.147	0.162	3-3/8	5-5/8	7-7/8	10-1/4	12-1/2
6-40	0.138	0.207	0.276	0.345	0.414	0.173	0.193	3-1/2	6	8-3/8	10-3/4	13-1/4
8-36	0.164	0.246	0.328	0.410	0.492	0.204	0.224	3-7/8	6-1/2	9-1/8	11-5/8	14-1/4
10-32	0.190	0.285	0.380	0.475	0.570	0.236	0.256	4-1/8	6-7/8	9-1/2	12-1/4	14-7/8
1/4-28	0.250	0.375	0.500	0.625	0.750	0.306	0.326	5	8-1/4	11-3/8	14-1/2	17-5/8
5/16-24	0.312	0.469	0.625	0.781	0.938	0.380	0.400	5-1/2	8-7/8	12-1/4	15-5/8	19
3/8-24	0.375	0.562	0.750	0.938	1.125	0.448	0.468	6-7/8	11	15	19-1/8	23-1/8
7/16-20	0.438	0.656	0.875	1.094	1.312	0.524	0.549	6-5/8	10-5/8	14-5/8	18-1/2	22-1/2
1/2-20	0.500	0.750	1.000	1.250	1.500	0.592	0.617	7-7/8	12-3/8	16-7/8	21-3/8	25-7/8
9/16-18	0.562	0.844	1.125	1.406	1.688	0.666	0.691	8	12-1/2	17-1/8	21-3/4	26-1/4
5/8-18	0.625	0.938	1.250	1.562	1.875	0.733	0.758	9	14-1/8	A9-1/4	24-1/4	29-3/8
3/4-16	0.750	1.125	1.500	1.875	2.250	0.876	0.901	9-3/4	15-1/8	20-5/8	26	31-1/2
7/8-14	0.875	1.312	1.750	2.188	2.625	1.021	1.051	9-7/8	15-1/2	21-1/8	26-5/8	32-1/4
1-12	1.000	1.500	2.000	2.500	3.000	1.169	1.199	9-5/8	15	20-1/2	26	31-1/2
1 1/8-12	1.125	1.688	2.250	2.812	3.375	1.304	1.334	11-1/8	17-1/4	23-3/8	29-1/2	35-3/4
1 1/4-12	1.250	1.875	2.500	3.125	3.750	1.439	1.469	12-1/2	19-3/8	26-1/4	33	39-7/8
1 3/8-12	1.375	2.062	2.750	3.438	4.125	1.575	1.610	13-3/4	21-3/8	28-7/8	36-1/2	44
1 1/2-12	1.500	2.250	3.000	3.750	4.500	1.710	1.745	15-1/4	23-1/2	31-5/8	39-7/8	48-1/8

Nominal Thread Size	Nominal Length*					Free Outside Diameter		Number of Free Coils**
	Length of Insert (in Diameter)					Free Outside Diameter		Nominal Length (Diameter)
	1	1 1/2	2	2 1/2	3	Min	Max	1	1 1/2	2	2 1/2	3
	Metric Coarse Series
M2X0.4	2	3	4	5	6	2.50	2.70	3-1/4	5-1/2	7-3/4	10-1/8	12-3/8
M2.2X0.45	2.2	3.3	4.4	5.5	6.6	2.80	3.00	3-1/8	5-3/8	7-5/8	9-7/8	12-1/8
M2.5X0.45	2.5	3.8	5.0	6.3	7.5	3.20	3.70	3-3/8	5-3/4	8-1/8	10-1/2	12-3/4
M3X0.5	3.0	4.5	6.0	7.5	9.0	3.80	4.35	3-3/4	6-3/8	8-7/8	11-3/8	13-7/8
M3.5X0.6	3.5	5.3	7.0	8.8	10.5	4.40	4.95	3-3/4	6-3/8	8-3/4	11-3/8	13-3/4
M4X0.7	4.0	6.0	8.0	10.0	12.0	5.05	5.60	3-5/8	6-1/8	8-5/8	11-1/8	13-5/8
M5X0.8	5.0	7.5	10.0	12.5	15.0	6.25	6.80	4-1/8	6-7/8	9-5/8	12-3/8	15-1/8
M6X1	6.0	9.0	12.0	15.0	18.0	7.40	7.95	4	6-3/4	9-1/2	12-1/8	14-7/8
M7X1	7.0	10.5	14.0	17.5	21.0	8.65	9.20	4-7/8	8	11-1/8	14-1/8	17-1/4
M8X1.25	8.0	12.0	16.0	20.0	24.0	9.80	10.35	4-1/2	7-3/8	10-1/4	13-1/4	16-1/8
M10X1.5	10.0	15.0	20.0	25.0	30.0	11.95	12.50	4-7/8	8	11-1/8	14-1/4	17-3/8
M12X1.75	12.0	18.0	24.0	30.0	36.0	14.30	15.00	5	8-1/4	11-1/2	14-5/8	17-7/8
M14X2	14.0	21.0	28.0	35.0	42.0	16.65	17.35	5-1/8	8-1/2	11-3/4	15	18-3/8
M16X2	16.0	24.0	32.0	40.0	48.0	18.90	19.60	6-1/8	9-3/4	13-1/2	17-1/4	21
M18X2.5	18.0	27.0	36.0	45.0	54.0	21.30	22.00	5-3/8	8-7/8	12-1/4	15-5/8	19
M20X2.5	20.0	30.0	40.0	50.0	60.0	23.55	24.40	6-1/8	9-7/8	13-5/8	17-3/8	21-1/8
M22X2.5	22.0	33.0	44.0	55.0	66.0	25.90	26.90	6-3/4	10-7/8	14-7/8	19	23-1/8
M24X3	24.0	36.0	48.0	60.0	72.0	28.00	29.00	6-1/8	10	13-3/4	17-1/2	21-3/8
M27X3	27.0	40.5	54.0	67.5	81.0	31.40	32.40	7	11-1/4	15-1/2	19-3/4	24
M30X3.5	30.0	45.0	60.0	75.0	90.0	34.80	36.00	6-3/4	10-3/4	14-7/8	18-7/8	23
M33X3.5	33.0	49.5	66.0	82.5	99.0	37.80	39.20	7-1/2	12	16-1/2	21	25-3/8
M36X4	36.0	54.0	72.0	90.0	108.0	41.50	42.90	7-1/8	11-3/8	15-5/8	19-7/8	24-1/4
M39X4	39.0	58.5	78.0	97.5	117.0	44.60	46.00	7-7/8	12-1/2	17-1/8	21-3/4	26-3/8
Metric Fine Series
M8X1	8.0	12.0	16.0	20.0	24.0	9.70	10.25	5-7/8	9-3/8	13	16-1/2	20-1/8
M10X1	10.0	15.0	20.0	25.0	30.0	11.95	12.50	7-5/8	12	16-1/2	21	25-1/2
M10X1.25	10.0	15.0	20.0	25.0	30.0	12.10	12.65	5-7/8	9-1/2	13-1/8	16-3/4	20-3/8
M12X1.25	12.0	18.0	24.0	30.0	36.0	14.30	15.00	7-1/4	11-5/8	15-7/8	20-1/4	24-1/2
M12X1.5	12.0	18.0	24.0	30.0	36.0	14.25	14.95	6	9-5/8	13-3/8	17	20-3/4
M14X1.5	14.0	21.0	28.0	35.0	42.0	16.55	17.25	7-1/8	11-3/8	15-5/8	20	24-1/4
M16X1.5	16.0	24.0	32.0	40.0	48.0	18.90	19.60	8-1/4	13-1/8	18	22-3/4	27-5/8
M18X1.5	18.0	27.0	36.0	45.0	54.0	21.05	21.75	9-1/2	15	20-3/8	25-7/8	31-3/8
M20X1.5	20.0	30.0	40.0	50.0	60.0	23.15	24.00	10-3/4	16-7/8	22-7/8	28-7/8	35
M22X1.5	22.0	33.0	44.0	55.0	66.0	25.55	26.45	11-7/8	18-1/2	25-1/8	31-5/8	38-1/4
M18X2	18.0	27.0	36.0	45.0	54.0	21.15	21.85	7	11-1/8	15-3/8	19-1/2	23-5/8
M20X2	20.0	30.0	40.0	50.0	60.0	23.20	24.05	7-7/8	12-1/2	17-1/4	27-7/8	26-1/2
M22X2	22.0	33.0	44.0	55.0	66.0	25.60	26.50	8-3/4	13-3/4	18-7/8	23-7/8	29
M24X2	24.0	36.0	48.0	60.0	72.0	28.10	29.10	9-1/2	15	20-3/8	25-7/8	31-3/4
M27X2	27.0	40.5	54.0	67.5	81.0	31.30	32.30	10-7/8	17	23-1/4	29-3/8	35-1/2
M30X2	30.0	45.0	60.0	75.0	90.0	34.50	35.70	12-1/4	19-1/8	25-7/8	32-3/4	39-1/2
M33X2	33.0	49.5	66.0	82.5	99.0	37.80	39.20	13-5/8	21-1/8	28-5/8	36	43-1/2
M36X2	36.0	54.0	72.0	90.0	108.0	41.00	42.40	15	23-1/4	31-3/8	39-1/2	47-3/4
M39X2	39.0	58.5	78.0	97.5	117.0	44.30	45.70	16-3/8	25-1/4	34-1/8	43	51-7/8
M36X3	36.0	54.0	72.0	90.0	108.0	41.30	42.70	9-3/4	15-1/4	20-7/8	26-1/2	32
M39X3	39.0	58.5	78.0	97.5	117.0	44.40	45.80	10-3/4	16-3/4	22-3/4	28-7/8	34-7/8

Notes:

Nominal length is a calculated number and cannot be measured in the free state. It is the actual installed length plus1/2 pitch.
Unified Sizes: The number of free coils is the total number of convolutions and has a tolerance of ±1/4 coil. Convolutions are counted by starting 90° from the tang for all Fine sizes and for Coarse sizes 5/8" and smaller. For coarse sizes 3/4" and up convolutions are counted by starting 180° from the tang.
Metric Sizes: The number of free coils is the total number of convolutions and has a tolerance of ±1/4 coil. Convolutions are counted by starting 90° from the tang for all Fine sizes and for Coarse sizes 16mm and smaller. For coarse sizes 18mm and up convolutions are counted by starting 180° from the tang.