M33 Fasteners | McMaster-Carr

These Grade 5 or Class 8 nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.

Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.

Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They offer minimal corrosion resistance, so they're best for dry environments.

Steel—Best for dry environments since moisture will cause these nuts to rust.

	Wd., mm	Ht., mm	Fastener Strength Grade/Class	Specs. Met	Pkg. Qty.		Pkg.
Zinc-Plated Steel



	M33 × 3.5 mm	50	26	Class 8	DIN 934	1	90591A147	00000


	Black-Oxide Steel



			M33 × 3.5 mm	50	26	Class 8	DIN 934	1	90593A018	00000


			Steel



					M33 × 2 mm	50	26	Class 8	DIN 934	1	91423A340	00000


					M33 × 3 mm	50	26	Class 8	DIN 934	1	91423A330	00000
					M33 × 3.5 mm	50	26	Class 8	DIN 934	1	90592A341	0000

Extreme-Strength Steel

These nuts are about 20% stronger than high-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.

Steel—Best for dry environments since moisture will cause these nuts to rust.

	Wd., mm	Ht., mm	Fastener Strength Grade/Class	Specs. Met	Pkg. Qty.		Pkg.
Steel



	M33 × 3.5 mm	50	26	Class 12	DIN 934	1	94223A112	000000

Corrosion-Resistant Stainless Steel

18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.

Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They resist rust in wet and outdoor environments, but won't hold up to the harsh chemicals that 316 stainless steel can.

Highly Corrosion-Resistant 316 Stainless Steel—Superior to 18-8 stainless steel, these nuts won't degrade when exposed to harsh weather, salt water, and most chemicals.

	Wd., mm	Ht., mm	Specs. Met	Pkg. Qty.		Pkg.
18-8 Stainless Steel



	M33 × 1.5 mm	50	24.7	DIN 934	1	93850A141	000000


	M33 × 3.5 mm	50	24.7	DIN 934	1	91828A112	00000


	Black-Oxide 18-8 Stainless Steel



			M33 × 1.5 mm	50	26	DIN 934	1	93850A132	00000


			M33 × 3.5 mm	50	26	DIN 934	1	98676A119	00000


			Highly Corrosion-Resistant 316 Stainless Steel



					M33 × 3.5 mm	50	26	DIN 934	1	94150A117	00000

Brass

Brass—Conductive and nonmagnetic, brass nuts are commonly used to secure electrical equipment, such as circuit board assemblies and mounting brackets, inside enclosures. They're also softer than most metals, so they won't damage other fastening components.

	Wd., mm	Ht., mm	Specs. Met	Pkg. Qty.		Pkg.
Brass



	M33 × 3.5 mm	50	26	DIN 934	1	90690A118	000000

Steel Socket Head Screws


Fully Threaded	Partially Threaded

Made of alloy steel, these screws are the standard for high-strength fastening. Use them in high-load applications such as dies, presses, and heavy equipment. The deep, six-point socket keeps the hex key from slipping out and damaging the drive.

Length is measured from under the head.

Black-Oxide Alloy Steel—Typically chosen for their appearance, these screws have a dark, matte coating to create a finished look. They offer minimal corrosion resistance, so they're best for dry environments.

		Head, mm
	Lg., mm	Dia.	Ht.	Threading	Thread Spacing	Tensile Strength, psi	Fastener Strength Grade/Class	Specs. Met	Pkg. Qty.		Pkg.
Black-Oxide Alloy Steel







				M33 × 3.5 mm

				100	50	33	Fully Threaded	Coarse	170,000	Class 12.9	DIN 912, ISO 4762	1	91290A283	000000


				120	50	33	Partially Threaded	Coarse	170,000	Class 12.9	DIN 912, ISO 4762	1	91290A284	00000

Thin-Profile Hex Nuts

About half the height of standard-profile nuts, these fit in spaces with low clearance. You can also use them as jam nuts by threading them against another hex nut to hold it in place.

Medium-Strength Steel

These Grade 5 or Class 04 nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.

Steel—Best for dry environments since moisture will cause these nuts to rust.

	Wd., mm	Ht., mm	Fastener Strength Grade/Class	Specs. Met	Pkg. Qty.		Pkg.
Steel



	M33 × 1.5 mm	50	14	—	DIN 936	1	90364A119	000000


	M33 × 2 mm	50	14	—	DIN 936	1	90364A118	0000
	M33 × 2 mm	50	16.5	Class 04	DIN 439B, ISO 4035	1	90326A223	00000
	M33 × 3.5 mm	50	14	—	DIN 936	1	90370A114	00000

Corrosion-Resistant Stainless Steel

18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.

Highly Corrosion-Resistant 316 Stainless Steel—Superior to 18-8 stainless steel, these nuts won't degrade when exposed to harsh weather, salt water, and most chemicals.

	Wd., mm	Ht., mm	Specs. Met	Pkg. Qty.		Pkg.
18-8 Stainless Steel



	M33 × 3.5 mm	50	14	DIN 936	1	90381A112	000000


	Highly Corrosion-Resistant 316 Stainless Steel



			M33 × 2 mm	50	16.5	DIN 439B, ISO 4035	1	97289A135	00000

Threaded Rods

Anchor, connect, or hang components in a wide variety of applications, from mounting I-beams to suspending light fixtures.

Medium-Strength Steel

Image of Product. Front orientation. Threaded Rods. Threaded Rods.

With tensile strengths from 110,000 psi to 125,000 psi, these rods are strong enough for most industrial applications, such as anchoring machinery and connecting pipe flanges. They are about twice as strong as low-strength steel rods. To avoid stripped threads during installation, make sure your nuts are also medium-strength steel.

Zinc-Plated Steel—The most common choice for areas with occasional exposure to moisture.

Steel—Best for dry environments since moisture will cause these rods to rust.

	Hardness	Specs. Met		Each
Zinc-Plated Steel







	M33 × 3.5 mm

	1 m	110,000	Class 8.8	Rockwell C20	DIN 976	99067A141	0000000


	Steel







					M33 × 3.5 mm

					300 mm	125,000	ASTM Grade B7	Rockwell C35	ASTM A193, DIN 976	93325A453	000000


					300 mm	110,000	Class 8.8	Rockwell C20	DIN 976	99055A339	00000
					1 m	125,000	ASTM Grade B7	Rockwell C35	ASTM A193, DIN 976	93325A454	000000
					1 m	110,000	Class 8.8	Rockwell C20	DIN 976	99055A341	000000
					2 m	125,000	ASTM Grade B7	Rockwell C35	ASTM A193, DIN 976	93325A455	000000

High-Strength Steel

With a tensile strength of 150,000 psi, these rods are strong enough to stabilize steel frameworks and structural supports, such as I-beams. They are about 25% stronger than medium-strength steel rods. To avoid stripped threads during installation, make sure your nuts are also high-strength steel.

Steel—Best for dry environments since moisture will cause these rods to rust.

	Hardness	Specs. Met		Each
Steel







	M33 × 3.5 mm

	1	150,000	Class 10.9	Rockwell C32	DIN 976	1078N99	0000000

Low-Strength Steel

With a tensile strength of 50,000 psi or 60,000 psi, these rods are often used to suspend light fixtures, cable trays, and conduit from ceilings. They're about half the strength of medium-strength steel rods. To avoid stripped threads during installation, make sure your nuts are also low-strength steel.

Zinc-Plated Steel—The most common choice for areas with occasional exposure to moisture.

Steel—Best for dry environments since moisture will cause these rods to rust.

	Specs. Met	Pkg. Qty.		Pkg.
Zinc-Plated Steel







	M33 × 3.5 mm

	300 mm	50,000	Rockwell B49	DIN 976	1	94595A251	0000000


	1 m	50,000	Rockwell B49	DIN 976	1	94595A252	000000


	Steel







					M33 × 3.5 mm

					300 mm	50,000	Rockwell B49	DIN 976	1	98861A235	00000


					1 m	50,000	Rockwell B49	DIN 976	1	98861A175	00000

Stainless Steel

More corrosion resistant than steel rods and comparable in strength to low-strength steel.

18-8 Stainless Steel—The choice for wet and outdoor environments, these rods resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.

	Specs. Met	Pkg. Qty.		Pkg.
18-8 Stainless Steel







	M33 × 3.5 mm

	1	70,000	Not Rated	DIN 976	1	90024A318	0000000

Shock Absorber Mounting Nuts

Hex Nuts

Use Mounting Blocks for Shock Absorbers (not included) to mount and secure threaded-body shock absorbers.

		Steel
	Thread Size		Each
Hex Nuts



		M33 × 1.5 mm	9530K84	000000

Heavy-Profile Hex Nuts

About 10% wider and taller than standard-profile hex nuts, these handle heavier loads by distributing them over a larger area.

Extreme-Strength Steel

These nuts are about 20% stronger than high-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.

Steel—Best for dry environments since moisture will cause these nuts to rust.

	Wd., mm	Ht., mm	Fastener Strength Grade/Class	Specs. Met	Pkg. Qty.		Pkg.
Steel



	M33 × 3.5 mm	55	33	ASTM Grade 2H	ASTM A194, DIN 6915	1	98498A116	000000

Stainless Steel Hex-Drive Shoulder Screws

These screws hold up against moisture and chemicals better than their steel counterparts, but they aren't as strong.

Check out our Made-to-Order Stainless Steel Hex-Drive Shoulder Screws if you don't see the shoulder length you need.

Highly Corrosion-Resistant Black-Oxide 316 Stainless Steel—Combines a finished appearance with the rust resistance of 316 stainless steel. Even if the coating wears off, these screws will hold up against corrosive agents in most environments, including salt water and most chemicals.

Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.

				Head, mm							Each
	Shoulder Lg., mm	Thread Size	Thread Lg., mm	Dia.	Ht.	Drive Size, mm	Tensile Strength, psi	Specs. Met	Material Certificate Form		1-4	5-Up
Highly Corrosion-Resistant Black-Oxide 316 Stainless Steel







				36 mm Diameter Shoulder (-0.072 mm to -0.01 mm Tolerance)

				50	M33 × 3.5 mm	40	54	22	17	70,000	ISO 7379	Digital	90269A946	000000	000000


				60	M33 × 3.5 mm	40	54	22	17	70,000	ISO 7379	Digital	90269A947	00000	00000
				70	M33 × 3.5 mm	40	54	22	17	70,000	ISO 7379	Digital	90269A949	00000	00000
				80	M33 × 3.5 mm	40	54	22	17	70,000	ISO 7379	Digital	90269A951	00000	00000
				90	M33 × 3.5 mm	40	54	22	17	70,000	ISO 7379	Digital	90269A953	00000	00000
				100	M33 × 3.5 mm	40	54	22	17	70,000	ISO 7379	Digital	90269A954	00000	00000
				120	M33 × 3.5 mm	40	54	22	17	70,000	ISO 7379	Digital	90269A955	00000	00000
				130	M33 × 3.5 mm	40	54	22	17	70,000	ISO 7379	Digital	90269A956	000000	000000
				140	M33 × 3.5 mm	40	54	22	17	70,000	ISO 7379	Digital	90269A957	000000	000000
				150	M33 × 3.5 mm	40	54	22	17	70,000	ISO 7379	Digital	90269A958	000000	000000

Coupling Nuts

Also known as extension nuts, these are commonly used to connect lengths of threaded rod and join threaded parts.

Corrosion-Resistant Stainless Steel

18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.

							Each
	Thread Size	Lg., mm	Wd., mm	Threading	Specs. Met		1-9	10-49	50-Up
18-8 Stainless Steel



		M33 × 3.5 mm	99	50	Fully Threaded	DIN 6334	93590A336	0000000	000000	000000

Key-Locking Threaded Insert Drivers

Place the tip of these tools into a key-locking insert after you've threaded it into a hole with your fingers. Then, strike these tools with a hammer to drive the keys into the material and secure the insert. They’re compatible with Keensert inserts.

Choose the tool that matches your insert’s thread size and tap thread size.

		Each
Metric Thread







	For Thick-Wall Inserts

	M24	M33	Straight	94010A365	000000

Key-Locking Threaded Insert Installation Tools


Style A	Style D

Thread inserts and drive down their keys with a single tool. These tools are compatible with Keensert inserts.

Threaded Insert Installation Tools

Style A

	For Tap Thread Size	Style	Features		Each
For Thick-Wall Inserts



	M24	M33	A	Slotted End	6721N93	000000

Threaded Insert Installation Tools with Spring

Style D

The tradespersons’ choice for installing Mil. Spec. inserts. A spring holds the sleeve under tension, so wobbles and jostles don’t interfere with a clean, professional install.

	For Tap Thread Size	Style	Features		Each
For Thick-Wall Inserts



	M24	M33	D	Sleeve, Slotted End	93904A798	000000

Left-Hand-Thread Thin-Profile Hex Nuts

These nuts tighten when turned to the left. Use them with left-hand rods and screws to prevent counterclockwise-moving parts from loosening. About half the height of standard-profile nuts, these fit in spaces with low clearance. You can also use them as jam nuts by threading them against another hex nut to hold it in place.

Medium-Strength Steel

These Grade 5 or Class 04 nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.

	Wd., mm	Ht., mm	Fastener Strength Grade/Class	Specs. Met	Pkg. Qty.		Pkg.
Black-Oxide Steel



	M33 × 3.5 mm	50	16.5	Class 04	ASTM A108, DIN 439B, ISO 4035	1	90519A827	000000

Nylon-Insert Locknuts

Versatile yet economical, these are the most commonly used locknuts. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.

High-Strength Steel

Image of Product. Front orientation. Locknuts. Nylon-Insert Locknuts.

Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.

Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.

	Wd., mm	Ht., mm	Fastener Strength Grade/Class	Insert Max. Temp., ° F	Specs. Met	Pkg. Qty.		Pkg.
Zinc-Plated Steel



	M33 × 3.5 mm	50	33	Class 10	220	DIN 985	1	94645A340	000000

Medium-Strength Steel

These Grade 5 or Class 8 nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.

Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.

	Wd., mm	Ht., mm	Fastener Strength Grade/Class	Insert Max. Temp., ° F	Specs. Met	Pkg. Qty.		Pkg.
Zinc-Plated Steel



	M33 × 2 mm	50	33	Class 8	220	DIN 985, ISO 10511	1	90576A384	000000


	M33 × 3.5 mm	50	33	Class 8	220	DIN 985, ISO 10511	1	90576A163	00000

Key-Locking Threaded Inserts with Installation Tools

Paired with the right tool for installation, these inserts create strong threads in soft metal, such as aluminum. They have keys that drive into material to prevent inserts from slipping and rotating in the hole.

Standard Wall—Stronger than thin-wall inserts, these are your go-to choice for threading most holes.

Black Phosphate-Coated Steel—These inserts resist occasional moisture.

	Drill Bit Size, mm	For Max. Hole Dia., mm	No. of Locking Keys	No. of Inserts Included		Each
Standard Wall







	Black Phosphate-Coated Steel

	M24 x 3 mm	M33 x 2 mm	33	31	31	4	2	90245A341	0000000

Screw-Locking Seize-Resistant Key-Locking Threaded Inserts for Soft Metal

Create the tightest hold in aluminum and other soft metal without screws sticking. The lubricant on these inserts eases installation, and the irregularly shaped threads won’t let screws back out from vibration. Inserts have keys that drive into material to prevent them from slipping or rotating in the hole.

To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.

Standard Wall—Stronger than thin-wall inserts, these are your go-to choice for threading most holes.

Dry-Film-Lubricated Cadmium-Plated Steel—The plating creates a barrier against rust.

	Inserts								Installation Tools
	Thread Size	For Tap Thread Size	Installed Lg., mm	Drill Bit Size, mm	For Max. Hole Dia., mm	No. of Locking Keys		Each		Each
Standard Wall







				Dry-Film-Lubricated Cadmium-Plated Steel

				M24 x 3 mm	M33 x 2 mm	33	31	31	4	97255A338	0000000	93904A798	000000

Key-Locking Threaded Inserts for Soft Metal

Add strong threads in soft metal, such as aluminum. The keys on these inserts drive into holes to hold more securely than thread-locking or helical inserts. They prevent slipping and rotating, so they’re stable enough for use in vehicle or aerospace parts that experience heavy vibration. These inserts are comparable to Keensert inserts.

Standard Wall—Stronger than thin-wall inserts, these are your go-to choice for threading most holes.

Black Phosphate-Coated Steel—These inserts resist occasional moisture.

18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.

	Inserts									Installation Tools		Inserts with Installation Tools
								Each
	Thread Size	For Tap Thread Size	Installed Lg., mm	Drill Bit Size, mm	For Max. Hole Dia., mm	No. of Locking Keys		1-9	10-Up		Each	No. of Inserts Included		Each
Standard Wall







				Black Phosphate-Coated Steel

				M24 x 2 mm	M33 x 2 mm	33	31	31	4	90245A217	000000	000000	94010A365	000000	—	———	0


				M24 x 3 mm	M33 x 2 mm	33	31	31	4	90245A213	00000	00000	94010A365	00000	2	90245A341	0000000




						18-8 Stainless Steel

						M24 x 3 mm	M33 x 2 mm	33	31	31	4	93715A685	00000	00000	94010A365	00000	—	———	0