Imperial Nut Information

Dimensional data charts for Imperial Nyloc, Full, Half and Castle Nuts[cite: 2].

Nyloc Nuts are also known as Prevailing Torque Nuts and Half Nuts are also known as Jam Nuts[cite: 2].

Dimensions shown are in Inches, if you wish to convert to mm, please use our universal converter[cite: 2].

NYLOC NUT DIMENSIONS - IMPERIAL

[cite: 2]

Nominal Size	Threads (BSW / BSF)	Across Flats (A/F)	Total Thickness
1/4"	20 / 26	0.525	0.328
5/16"	18 / 22	0.600	0.359
3/8"	16 / 20	0.710	0.422
7/16"	14 / 18	0.820	0.469
1/2"	12 / 16	0.920	0.609
5/8"	11 / 14	1.100	0.750
3/4"	10 / 12	1.300	0.891

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FULL NUT DIMENSIONS - IMPERIAL - BS1083 1965

[cite: 2]

Nominal Size	Threads (BSW / BSF)	Across Flats (A/F)	Thickness
1/4"	20 / 26	0.525	0.190
5/16"	18 / 22	0.600	0.250
3/8"	16 / 20	0.710	0.312
7/16"	14 / 18	0.820	0.375
1/2"	12 / 16	0.920	0.438
5/8"	11 / 14	1.100	0.562
3/4"	10 / 12	1.300	0.688

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HALF NUT DIMENSIONS - IMPERIAL - BS1083 1965

[cite: 2]

Nominal Size	Threads (BSW / BSF)	Across Flats (A/F)	Thickness
1/4"	20 / 26	0.525	0.125
5/16"	18 / 22	0.600	0.156
3/8"	16 / 20	0.710	0.188
7/16"	14 / 18	0.820	0.219
1/2"	12 / 16	0.920	0.250
5/8"	11 / 14	1.100	0.312
3/4"	10 / 12	1.300	0.375

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CASTLE NUT DIMENSIONS - IMPERIAL - BS1083 1965

[cite: 2]

Nominal Size	Threads (BSW / BSF)	Across Flats (A/F)	Total Thickness	Slot Width
1/4"	20 / 26	0.525	0.312	0.094
5/16"	18 / 22	0.600	0.406	0.094
3/8"	16 / 20	0.710	0.469	0.125
7/16"	14 / 18	0.820	0.562	0.125
1/2"	12 / 16	0.920	0.625	0.156
5/8"	11 / 14	1.100	0.781	0.188
3/4"	10 / 12	1.300	0.938	0.188