Flat-Top Square Nuts | McMaster-Carr

Filter by

Thread Size

Width

Height

Material

Finish

Thread Spacing

Thread Type

REACH

RoHS

Compliant with Exemptions

Export Control Classification Number (ECCN)

EAR99

DFARS Specialty Metals

47 Products

Low-Strength Steel Square Nuts

Large flat sides make these nuts easy to grip with a wrench and keep them from rotating in channels and square holes. About half the strength of medium-strength steel square nuts, use them in light duty fastening applications, such as securing access panels.

Zinc-Plated Steel—Zinc-plated steel square nuts resist corrosion in wet environments.

Black-Zinc-Plated Steel—Black-zinc-plated steel square nuts resist corrosion in wet environments and have a black finish that blends in with dark surfaces.

Steel—Steel square nuts are best for dry environments, since moisture will cause them to rust.

	Wd.	Ht.	Pkg. Qty.		Pkg.
Zinc-Plated Steel



	2-56	3/16"	1/16"	100	000000000	00000


	4-40	1/4"	3/32"	100	000000000	0000
	5-40	5/16"	7/64"	100	000000000	0000
	6-32	5/16"	7/64"	100	000000000	0000
	8-32	11/32"	1/8"	100	000000000	0000
	10-24	3/8"	1/8"	100	000000000	0000
	10-32	3/8"	1/8"	100	000000000	0000
	1/4"-20	7/16"	3/16"	100	000000000	0000
	1/4"-28	7/16"	3/16"	100	000000000	00000
	5/16"-18	9/16"	7/32"	100	000000000	00000
	3/8"-16	5/8"	1/4"	50	000000000	00000


	1/2"-13	13/16"	7/16"	25	000000000	0000
	5/8"-11	1"	35/64"	25	000000000	00000
	3/4"-10	1 1/8"	21/32"	10	000000000	0000
	1"-8	1 1/2"	7/8"	5	000000000	00000


	Black-Zinc-Plated Steel



			1/4"-20	7/16"	3/16"	100	000000000	00000


			5/16"-18	9/16"	7/32"	50	000000000	00000
			3/8"-16	5/8"	1/4"	50	000000000	00000


			Steel



					6-32	5/16"	7/64"	100	000000000	0000


					8-32	11/32"	1/8"	100	000000000	0000
					10-24	3/8"	1/8"	100	000000000	0000
					10-32	3/8"	1/8"	100	000000000	0000
					1/4"-20	7/16"	3/16"	100	000000000	00000
					5/16"-18	9/16"	7/32"	100	000000000	00000
					3/8"-16	5/8"	1/4"	100	000000000	00000

Highly-Corrosion-Resistant 316 Stainless Steel Square Nuts

These square nuts have excellent resistance to chemicals and salt water. Large flat sides make them easy to grip with a wrench and keep them from rotating in channels and square holes.

	Wd.	Ht.	Pkg. Qty.		Pkg.
316 Stainless Steel



	4-40	1/4"	3/32"	100	000000000	000000


	6-32	5/16"	7/64"	100	000000000	00000
	8-32	11/32"	1/8"	50	000000000	00000
	10-24	3/8"	1/8"	50	000000000	00000
	10-32	3/8"	1/8"	50	000000000	00000
	1/4"-28	7/16"	3/16"	25	000000000	0000
	5/8"-11	1"	35/64"	1	000000000	0000
	3/4"-10	1 1/8"	21/32"	1	000000000	00000

Brass Square Nuts

These square nuts are corrosion resistant in wet environments, electrically conductive, and nonmagnetic. Large flat sides make them easy to grip with a wrench and keep them from rotating in channels and square holes.

	Wd.	Ht.	Pkg. Qty.		Pkg.
Brass



	4-40	1/4"	3/32"	100	000000000	00000


	6-32	5/16"	7/64"	100	000000000	00000
	8-32	11/32"	1/8"	50	000000000	0000
	10-24	3/8"	1/8"	50	000000000	00000
	10-32	3/8"	1/8"	50	000000000	00000
	1/4"-20	7/16"	3/16"	25	000000000	00000
	5/16"-18	9/16"	7/32"	10	000000000	0000
	3/8"-16	5/8"	1/4"	10	000000000	00000
	1/2"-13	13/16"	7/16"	5	000000000	00000

Fiberglass Square Nuts

These fiberglass square nuts are chemical resistant, nonconductive, and lightweight. Large flat sides make them easy to grip with a wrench and keep them from rotating in channels and square holes.

	Wd.	Ht.	Max. Temp.	Color	Pkg. Qty.		Pkg.
Fiberglass



	3/8"-16	3/4"	17/32"	Not Rated	Gray	1	000000000	00000


	1/2"-13	7/8"	41/64"	Not Rated	Gray	1	000000000	0000
	5/8"-11	1 1/8"	51/64"	Not Rated	Gray	1	000000000	0000
	3/4"-10	1 1/4"	57/64"	Not Rated	Gray	1	000000000	0000
	1"-8	1 11/16"	1 9/64"	Not Rated	Gray	1	000000000	00000