NASM21046 Locknuts | McMaster-Carr

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6 Products

Mil. Spec. Flex-Top Locknuts for Heavy Vibration

These locknuts are manufactured and tested to strict U.S. military standards for material and construction. The top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.

Corrosion-Resistant Stainless Steel

Image of Product. Front orientation. Locknuts. Mil. Spec. Flex-Top Locknuts for Heavy Vibration.

Silver-Plated 18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts won't rust. The silver plating adds lubricity to help them thread on smoothly during installation.

	Wd.	Ht.	Mil. Spec.	Certificate Type	Pkg. Qty.		Pkg.
Silver-Plated 18-8 Stainless Steel



	4-40	1/4"	9/64"	MS21046C04, NASM21046	Material Certificate	1	99851A101	000000


	6-32	5/16"	11/64"	MS21046C06, NASM21046	—	1	99851A102	00000
	8-32	11/32"	15/64"	MS21046C08, NASM21046	—	1	99851A103	0000
	10-32	3/8"	15/64"	MS21046C3, NASM21046	—	1	99851A104	00000
	1/4"-28	7/16"	9/32"	MS21046C4, NASM21046	—	1	99851A105	00000
	3/8"-24	9/16"	25/64"	MS21046C6, NASM21046	Material Certificate	1	99851A106	00000