ASME B5.1M T-Bolts

                                                                                                                                                                 

Nominal T-Bolt Size and Thread A2 ab		Bolt Head Dimensions										Rounding of Cornersc
		Width Across Flats B2				Width Across Corners		Height C2				R2		W2
inch UNC-2A	metric ISOd	inch		mm		inch	mm	inch		mm		inch	mm	inch	mm
		max	min	max	min	max	max	max	min	max	min	max	max	max	max
. . .	M4	. . .	. . .	9	8.5	. . .	12.7	. . .	. . .	2.5	2.1	. . .	0.3	. . .	0.5
. . .	M5	. . .	. . .	10	9.5	. . .	14.1	. . .	. . .	4	3.6	. . .	0.3	. . .	0.5
0.250-20	M6	0.469	0.438	13	12	0.663	18.4	0.156	0.141	6	5.6	0.02	0.5	0.03	0.8
0.312-18	M8	0.562	0.531	15	14	0.796	21.2	0.188	0.172	6	5.6	0.02	0.5	0.03	0.8
0.375-16	M10	0.688	0.656	18	17	0.972	25.5	0.25	0.234	7	6.6	0.02	0.5	0.03	0.8
0.500-13	M12	0.875	0.844	22	21	1.238	31.1	0.312	0.297	8	7.6	0.02	0.5	0.06	1.5
0.625-11	M16	1.125	1.094	28	27	1.591	39.6	0.406	0.391	10	9.6	0.03	0.8	0.06	1.5
0.750-10	M20	1.312	1.281	34	33	1.856	48.1	0.531	0.5	14	13.2	0.03	0.8	0.06	1.5
1.000-8	M24	1.688	1.656	43	42	2.387	60.8	0.688	0.656	18	17.2	0.03	0.8	0.06	1.5
1.250-7	M30	2.062	2.031	53	52	2.917	75	0.938	0.906	23	22.2	0.03	0.8	0.06	1.5
1.500-6	M36	2.5	2.469	64	63	3.536	90.5	1.188	1.156	28	27.2	0.03	0.8	0.06	1.5
. . .	M42	. . .	. . .	75	74	. . .	106.1	. . .	. . .	32	30.5	. . .	1	. . .	2
. . .	M48	. . .	. . .	85	84	. . .	120.2	. . .	. . .	36	34.5	. . .	1	. . .	2
a For inch tolerances for thread diameters of bolts or studs and for threads see page 1736. b T-slots to be used with these bolts will be found in Table 1. c Corners of T-bolts may be square or may be rounded or broken to the indicated maximum dimensions at the manufacturer's option. d Metric thread grade and tolerance position is 5g 6g (see page 1790).