Tamper-Resistant Nuts | McMaster-Carr

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78 Products

Tri-Groove-Drive Tamper-Resistant Nuts

Tri-groove-drive nuts are narrower than sloped and drilled-spanner-drive nuts to fit in tight spaces. Install with a tri-groove socket and either a socket driver or an open-end wrench (all sold separately). Use them to reduce the risk of unwanted removal for objects in public spaces such as signs, lighting fixtures, and displays.

Zinc—Zinc nuts are lightweight and corrosion resistant in wet environments.

Zinc-Plated Steel—Zinc-plated steel nuts are coated to protect the steel from corrosion in wet environments.

316 Stainless Steel—316 stainless steel nuts won’t corrode from water, chemicals, or salt spray.

	Nuts						Tri-Groove Sockets		Socket Drivers		Open-End Wrenches
	Thread Size	Dia.	Ht.	Pkg. Qty.		Pkg.		Each		Each		Each
Zinc



		M6 × 1 mm	0.66"	0.265"	10	000000000	00000	0000000	000000	0000000	000000	———	0


		M8 × 1.25 mm	0.83"	0.345"	10	000000000	0000	0000000	00000	0000000	00000	———	0


		Zinc-Plated Steel



				10-24	0.64"	0.265"	25	000000000	00000	0000000	00000	0000000	00000	———	0


				10-32	0.64"	0.265"	25	000000000	00000	0000000	00000	0000000	00000	———	0
				1/4"-20	0.64"	0.265"	25	000000000	00000	0000000	00000	0000000	00000	———	0
				5/16"-18	0.83"	0.345"	25	000000000	00000	0000000	00000	0000000	00000	———	0
				3/8"-16	0.83"	0.345"	25	000000000	00000	0000000	00000	0000000	00000	———	0


				316 Stainless Steel



						10-24	0.65"	0.265"	10	000000000	00000	0000000	00000	0000000	00000	———	0


						10-32	0.65"	0.265"	10	000000000	00000	0000000	00000	0000000	00000	———	0
						1/4"-20	0.66"	0.265"	10	000000000	00000	0000000	00000	0000000	00000	———	0
						1/4"-28	0.65"	0.265"	10	000000000	00000	0000000	00000	0000000	00000	———	0
						5/16"-18	0.83"	0.345"	10	000000000	00000	0000000	00000	0000000	00000	———	0
						5/16"-24	0.83"	0.35"	5	000000000	00000	0000000	00000	0000000	00000	———	0
						3/8"-16	0.83"	0.345"	10	000000000	00000	0000000	00000	0000000	00000	———	0
						3/8"-24	0.83"	0.35"	5	000000000	00000	0000000	00000	0000000	00000	———	0
						7/16"-14	0.83"	0.34"	1	000000000	0000	0000000	00000	0000000	00000	———	0
						1/2"-13	0.93"	0.345"	1	000000000	0000	00000000	00000	0000000	00000	———	0
						1/2"-20	0.93"	0.345"	1	000000000	0000	00000000	00000	0000000	00000	———	0


						5/8"-11	1.51"	0.505"	1	000000000	00000	0000000	000000	———	0	0000000	000000
						5/8"-18	1.51"	0.505"	1	000000000	00000	0000000	000000	———	0	0000000	00000
						3/4"-10	1.51"	0.505"	1	000000000	00000	0000000	000000	———	0	0000000	00000
						3/4"-16	1.51"	0.505"	1	000000000	00000	0000000	000000	———	0	0000000	00000
						M5 × 0.8 mm	0.66"	0.265"	5	000000000	00000	0000000	00000	0000000	00000	———	0
						M6 × 1 mm	0.66"	0.265"	5	000000000	00000	0000000	00000	0000000	00000	———	0
						M8 × 1 mm	0.82"	0.35"	1	000000000	0000	0000000	00000	0000000	00000	———	0
						M8 × 1.25 mm	0.82"	0.35"	5	000000000	00000	0000000	00000	0000000	00000	———	0
						M10 × 1.25 mm	0.82"	0.35"	1	000000000	0000	0000000	00000	0000000	00000	———	0
						M10 × 1.5 mm	0.82"	0.35"	1	000000000	0000	0000000	00000	0000000	00000	———	0


						M12 × 1.5 mm	0.94"	0.35"	1	000000000	0000	00000000	00000	0000000	00000	———	0
						M12 × 1.75 mm	0.94"	0.35"	1	000000000	0000	00000000	00000	0000000	00000	———	0
						M16 × 2 mm	1.51"	0.505"	1	000000000	00000	0000000	000000	———	0	0000000	00000

Breakaway Tamper-Resistant Nuts


	Aluminum	Zinc	Zinc-Plated Alloy Steel	18-8 Stainless Steel

The most tamper-resistant nuts we offer, these have a hex head that breaks away upon tightening, leaving a non-removable cone. They can be installed using a standard wrench. Use them to reduce the risk of unwanted removal for objects in public spaces such as signs, lighting fixtures, and displays.

Aluminum—Aluminum nuts are lightweight, corrosion resistant in wet environments, and nonmagnetic.

Zinc and Zinc-Plated Alloy Steel—Zinc and zinc-plated alloy steel nuts are corrosion resistant in wet environments.

18-8 Stainless Steel—18-8 stainless steel nuts have good chemical resistance and may be mildly magnetic.

	Wd.	Ht.	Ht. After Installation	Breaking Torque, in·lbf	Pkg. Qty.		Pkg.
Aluminum



	10-24	7/16"	3/8"	3/16"	40	10	000000000	00000


	1/4"-20	9/16"	31/64"	7/32"	70	10	000000000	0000
	5/16"-18	5/8"	1/2"	7/32"	150	10	000000000	00000
	3/8"-16	3/4"	19/32"	1/4"	195	10	000000000	00000


	Zinc



			10-24	7/16"	25/64"	3/16"	40	10	000000000	00000


			1/4"-20	9/16"	15/32"	7/32"	60	10	000000000	00000
			5/16"-18	5/8"	1/2"	7/32"	110	10	000000000	00000
			3/8"-16	3/4"	37/64"	1/4"	150	10	000000000	00000
			1/2"-13	1"	3/4"	11/32"	360	5	000000000	00000
			5/8"-11	1 1/8"	51/64"	3/8"	360	5	000000000	00000
			M6 × 1 mm	14 mm	12 mm	6 mm	60	10	000000000	00000
			M8 × 1.25 mm	16 mm	13 mm	6 mm	110	10	000000000	00000
			M10 × 1.5 mm	19 mm	15 mm	6 mm	150	5	000000000	00000
			M12 × 1.75 mm	25 mm	19 mm	9 mm	360	5	000000000	00000


			Zinc-Plated Alloy Steel



					3/4"-10	1 1/4"	1"	13/32"	1,500	100	000000000	000000


					18-8 Stainless Steel



							1/4"-20	9/16"	15/32"	7/32"	95	5	000000000	00000


							5/16"-18	5/8"	1/2"	7/32"	130	5	000000000	00000
							3/8"-16	3/4"	37/64"	1/4"	245	5	000000000	00000
							1/2"-13	1"	3/4"	11/32"	405	100	000000000	000000
							5/8"-11	1 1/8"	51/64"	3/8"	510	50	000000000	000000
							M6 × 1 mm	10 mm	10 mm	5 mm	85	10	000000000	00000
							M8 × 1.25 mm	13 mm	12 mm	7 mm	185	10	000000000	00000
							M10 × 1.5 mm	17 mm	15 mm	9 mm	350	5	000000000	00000
							M12 × 1.75 mm	19 mm	16 mm	9 mm	395	5	000000000	00000

Drilled-Spanner-Drive Tamper-Resistant Nuts

A wide base and large bearing surface make these nuts good for securing large objects. They must be installed and removed with a nutdriver (sold separately). Use them to reduce the risk of unwanted removal for objects in public spaces such as signs, lighting fixtures, and displays.

Zinc—Made from zinc, they're corrosion resistant in wet environments.

	Nuts						Spanner Nutdrivers
	Thread Size	Dia.	Ht.	Pkg. Qty.		Pkg.		Each
Zinc



		1/4"-20	1"	1/4"	10	000000000	000000	000000000	000000


		5/16"-18	1"	1/4"	10	000000000	00000	000000000	00000
		3/8"-16	1"	1/4"	10	000000000	00000	000000000	00000
		M6 × 1 mm	1"	1/4"	10	000000000	00000	000000000	00000
		M8 × 1.25 mm	1"	1/4"	10	000000000	00000	000000000	00000
		M10 × 1.5 mm	1"	1/4"	10	000000000	00000	000000000	00000

Sloped Tamper-Resistant Nuts

Image of ProductInUse. Front orientation. Tamper-Resistant Nuts. Sloped Surface.

Sloped sides make these nuts difficult to grasp with standard hand tools to reduce the risk of unwanted removal. To install, thread a second sloped nut onto the bolt upside down and insert a wrench between the two nuts to fasten. They're often used to secure signs, lighting fixtures, and displays in public spaces.

Zinc-Yellow-Chromate-Plated Steel—A zinc yellow-chromate plating provides corrosion resistance in wet environments.

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



	1/4"-20	1 3/64"	15/64"	5	000000000	00000


	5/16"-18	1 3/64"	15/64"	5	000000000	0000
	3/8"-16	1 3/64"	15/64"	5	000000000	0000
	M6 × 1 mm	1 3/64"	15/64"	5	000000000	0000
	M8 × 1.25 mm	1 3/64"	15/64"	5	000000000	0000
	M10 × 1.5 mm	1 3/64"	15/64"	5	000000000	0000

Serrated-Edge-Drive Tamper-Resistant Nuts

These nuts have serrations that dig into the material surface to resist loosening and are narrow to fit in tight spaces. They must be installed with a nutdriver (sold separately). Use them to reduce the risk of unwanted removal for objects in public spaces such as signs, lighting fixtures, and displays.

Aluminum—Aluminum nuts are lightweight, corrosion resistant in wet environments, and nonmagnetic.

	Nuts						Serrated-Edge Nutdrivers
	Thread Size	Dia.	Ht.	Pkg. Qty.		Pkg.		Each
Aluminum



		10-24	1/2"	3/16"	25	000000000	000000	000000000	000000


		1/4"-20	1/2"	3/16"	10	000000000	0000	000000000	00000
		5/16"-18	1/2"	3/16"	10	000000000	0000	000000000	00000