2 1/2"-4 Nuts | McMaster-Carr

Also known as jam nuts, these are about half the height of standard hex nuts. Use them in low-clearance applications or jam one against another nut to hold it in place. About half the strength of medium-strength steel thin nuts, use them for light duty fastening applications, such as securing access panels.

For technical drawings and 3-D models, click on a part number.

Steel—Grade 2
Thread Size	Wd.	Ht.	Pkg. Qty.		Pkg.
2 1/2"-4	3 3/4"	1 13/32"	1	000000000	000000

Extreme-Strength Steel Extra-Wide Hex Nuts—Grade 2H

Also known as heavy hex nuts, these nuts are about 10% wider and taller than standard hex nuts and distribute the load over a large area. Grade 2H nuts are comparable in strength to Grade 9 bolts. They're about 20% stronger than high-strength steel nuts and are used in heavy machinery, such as earth-moving equipment.

For technical drawings and 3-D models, click on a part number.

Steel—Grade 2H
Thread Size	Wd.	Ht.	Specifications Met	Pkg. Qty.		Pkg.
2 1/2"-4	3 7/8"	2 29/64"	ASME B18.2.2, ASTM A194	1	000000000	000000

Medium-Strength Steel Extra-Wide Hex Nuts—Grade 5

About 10% wider and taller than standard hex nuts, these nuts distribute the load over a large area. They're also known as heavy hex nuts. Medium-strength steel nuts are suitable for fastening most machinery and equipment.

For technical drawings and 3-D models, click on a part number.

Steel—Grade 5
Thread Size	Wd.	Ht.	Pkg. Qty.		Pkg.
2 1/2"-4	3 7/8"	2 29/64"	1	000000000	000000

Low-Strength Steel Extra-Wide Thin Hex Nuts

Also known as heavy jam nuts, these are about half the height and 10% wider than standard hex nuts. Use them in low-clearance applications or jam against another extra-wide hex nut to hold it in place. Made from low-strength steel, use them in light duty fastening applications, such as securing access panels.

For technical drawings and 3-D models, click on a part number.

Steel—Grade 2
Thread Size	Wd.	Ht.	Pkg. Qty.		Pkg.
2 1/2"-4	3 7/8"	1 29/64"	1	000000000	000000

Low-Strength Steel Coupling Nuts

Also known as extension nuts, use these to connect and extend threaded rods. They're about half the strength of medium-strength steel coupling nuts for use in light duty fastening applications.

Zinc-plated steel coupling nuts resist corrosion in wet environments.

For technical drawings and 3-D models, click on a part number.

				Each
Thread Size	Lg.	Wd.		1-9	10-Up
Zinc-Plated Steel
2 1/2"-4	5 1/2"	3 1/2"	000000000	0000000	000000

Steel Extra-Long Coupling Nuts

Also known as sleeve nuts, these are at least twice the length of standard coupling nuts to provide more room to connect and extend long lengths of threaded rods.

For technical drawings and 3-D models, click on a part number.

				Each
Thread Size	Lg.	Wd.		1-9	10-Up
Steel
2 1/2"-4	10"	4"	000000000	0000000	0000000

Left-Hand to Right-Hand Female Hex Thread Adapters

Often called sleeve nuts, these thread adapters fasten parts with right-hand threads to parts with left-hand threads.

Zinc-plated steel adapters are strong and corrosion resistant.

For technical drawings and 3-D models, click on a part number.

Inch

Thread Size		Thread Lg.		Thread Fit		Hex				Each
(A)	(B)	(A)	(B)	(A)	(B)	Size	Lg.	Hardness		1-9	10-Up
Zinc-Plated Steel
2 1/2"-4	2 1/2"-4	4 3/4"	4 3/4"	Class 2B	Class 2B	4"	10"	Rockwell B65	000000000	0000000	0000000

Acme Lead Screws and Nuts

Found in hand-powered clamps, vises, grates, doors, and work tables, lead screws and nuts have broad, square threads that are well suited for quick assembly, high clamping forces, and lifting and lowering heavy objects. To ensure compatibility, please select components that have the same thread direction and size.

Carbon steel components are easier to machine than alloy steel components. Zinc-plated carbon steel components have mild corrosion resistance. Alloy steel components are harder and stronger than carbon steel components. 360 brass components have excellent machinability and good corrosion resistance. 18-8 stainless steel components have good corrosion resistance.

Travel distance per turn, also known as screw lead, is the distance a nut or handle moves with one revolution of the lead screw.

For technical drawings and 3-D models, click on a part number.

Lead Screws—Right-Hand Threaded

Carbon Steel
Thread Size	Lg.	No. of Thread Starts	Speed Ratio	Travel Distance per Turn	Thread Fit	Fastener Strength Grade/Class	Hardness	Tensile Strength, psi	Specifications Met		Each
2 1/2"-4	12"	1	1:1	0.25"	Class 2G	Grade 2	Rockwell B61	53,000	ASTM A108	000000000	000000
2 1/2"-4	3 ft.	1	1:1	0.25"	Class 2G	Grade 2	Rockwell B61	53,000	ASTM A108	000000000	000000
2 1/2"-4	6 ft.	1	1:1	0.25"	Class 2G	Grade 2	Rockwell B61	53,000	ASTM A108	000000000	000000
Alloy Steel
2 1/2"-4	3 ft.	1	1:1	0.25"	Class 2G	Grade B7	Rockwell C35	125,000	ASTM A193	000000000	000000

Coupling Nuts—Right-Hand Threaded

Coupling nuts connect two lead screws.

Carbon Steel
Thread Size	Ht.	Wd.	No. of Thread Starts	Speed Ratio	Travel Distance per Turn	Thread Fit	Hardness		Each
2 1/2"-4	5"	3 1/2"	1	1:1	0.25"	Class 2G	Rockwell B75	000000000	0000000

Hex Nuts—Right-Hand Threaded

Hex nuts fasten and position lead screw components.

Carbon Steel
Thread Size	Ht.	Wd.	No. of Thread Starts	Speed Ratio	Travel Distance per Turn	Thread Fit	Hardness	Specifications Met		Each
2 1/2"-4	2 1/2"	3 1/2"	1	1:1	0.25"	Class 2G	Rockwell B75	__	000000000	000000
Zinc-Plated Carbon Steel
2 1/2"-4	2 1/2"	3 1/2"	1	1:1	0.25"	Class 2G	Rockwell B75	__	000000000	000000
360 Brass
2 1/2"-4	2 1/2"	3 1/2"	1	1:1	0.25"	Class 2G	Rockwell B75	ASTM B16	000000000	000000
18-8 Stainless Steel
2 1/2"-4	2 1/2"	3 1/2"	1	1:1	0.25"	Class 2G	Rockwell B97	__	000000000	000000

Precision Acme Lead Screws and Nuts

Pair with a motor in automated motion and positioning applications. A tight thread fit allows these lead screws and nuts to make accurate, repeatable starts and stops. Also known as single-start and self-locking lead screws and nuts, they have a single thread that runs the length of the screw. The nut travels only when the screw turns, so your system won’t unexpectedly move when the lead screw is at rest. To ensure compatibility, please select components that have the same thread direction and size.

Carbon steel lead screws and flanges have good machinability. 932 bearing bronze and 673 bronze nuts are wear resistant. They have good machinability and fair corrosion resistance.

Travel distance per turn, also known as screw lead, is the distance a nut moves with one revolution of the lead screw.

For technical drawings and 3-D models, click on a part number.

Lead Screws—Right-Hand Threaded

Right-Hand Threads

1018 Carbon Steel
Thread Size	Lg.	No. of Thread Starts	Speed Ratio	Travel Distance per Turn	Accuracy for Travel Distance per Turn	Thread Fit	Hardness	Tensile Strength, psi		Each
2 1/2"-4	3 ft.	1	1:1	0.25"	±0.009" per ft.	Class 2C	Brinell 126	64,000	000000000	0000000
2 1/2"-4	6 ft.	1	1:1	0.25"	±0.009" per ft.	Class 2C	Brinell 126	64,000	000000000	000000

Externally Threaded Nuts—Right-Hand Threaded

Combine externally threaded nuts with a flange to create a custom flange nut.

						External Thread
Thread Size	Lg.	Dia.	No. of Thread Starts	Speed Ratio	Travel Distance per Turn	Size	Lg.	Thread Fit	Hardness	Dynamic Thrust Load Cap., lbs.		Each
673 Bronze
2 1/2"-4	3 3/8"	3.375"	1	1:1	0.25"	3 9/64"-12	1 9/16"	Class 2C	Brinell 70	Not Rated	000000000	0000000