Nuts Back Hex Machine Screw Nuts Steel, Zinc Plated Hex Machine Screw Nuts Small Pattern Steel, Zinc Plated Nylon Insert Stop Nuts Steel, Zinc Plated Nylon Insert Thin Pattern Stop Nuts Steel, Zinc Plated Grade 5 Hex Panel Nuts Steel, Zinc Plated Size Size Size Size Size (All sizes up to and including 1" diameter are domestic.) 0-80 1-72 2-56 3-48 4-40 5-40 6-32 8-32 10-24 10-32 12-24 1/4-20 1/4-28 5/16-18 3/8-16 4-40 X 3/16 6-32 X 1/4 8-32 X 1/4 8-32 X 5/16 10-32 X 5/16 2-56 NM 4-40 NM 5-40 NM 6-32 NM 8-32 NM 10-24 NM 10-32 NM 1/4-20 NE 1/4-28 NE 5/16-18 NE 5/16-24 NE 3/8-16 NE 3/8-24 NE 7/16-14 NE 7/16-20 NE 1/2-13 NE 1/2-20 NE 9/16-12 NE 9/16-18 NE 5/8-11 NE 5/8-18 NE 3/4-10 NE 3/4-16 NE 7/8-9 NE 7/8-14 NE 1-8 NE 1-14 NE 1 1/8-7 NE 1 1/4-7 NE 1 1/4-12 NE 1 1/2-6 NE 4-40 NTM 6-32 NTM 8-32 NTM 10-24 NTM 10-32 NTM 1/4-20 NTE 1/4-28 NTE 5/16-18 NTE 5/16-24 NTE 3/8-16 NTE 3/8-24 NTE 7/16-14 NTE 7/16-20 NTE 1/2-13 NTE 1/2-20 NTE 5/8-11 NTE 5/8-18 NTE 3/4-10 NTE 3/4-16 NTE Thread Size x Thickness 1/8-27 X 1/8 1/8-27 X 3/16 Thread Size x Across the Flats 3/8-32 X 1/2 3/8-32 X 9/16 15/32-32 X 9/16