M25 Bushings | McMaster-Carr

With a nylon insert that grips your threaded shaft or spindle without damaging the threads, these locknuts—sometimes called shaft nuts—keep bearings, bushings, gears, and pulleys in place. They won’t shake loose from vibration. However, their nylon insert also means you shouldn’t use these locknuts in applications with high temperatures. Their sides are slotted, so you can tighten and loosen them with a spanner wrench or spanner socket. To reduce the total size and weight of your assembly, they have chamfered edges.

All meet international standards for bearing locknut dimensions.

Carbon steel locknuts are strong and wear resistant. Zinc-plated steel locknuts have an outer layer of zinc that prevents the steel from rusting in wet areas. Compared to stainless steel, they're stronger, more wear resistant, and less costly, but not as corrosion resistant. Avoid exposing them to salt water and chemicals. 303 stainless steel locknuts are nearly as strong as carbon steel but won’t rust in outdoor, washdown, and other corrosive environments.

When choosing your thread spacing, consider the precision of your application. The finer the threads, the more control you have when making adjustments.

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

Metric

Locknuts
Thread									Spanner Sockets
Size	Pitch, mm	Spacing	OD	Wd., mm	Insert Max. Temp., °F	Specifications Met		Each		Each
Carbon Steel
Chamfered Face
M25	1.5	Extra Fine	38mm	11	160°	ISO 2982-2	0000000	000000	00000000	0000000
Zinc-Plated Carbon Steel
Chamfered Face
M25	1.5	Extra Fine	38mm	10.5	210°	DIN 1805	0000000	00000	000000	00
303 Stainless Steel
Chamfered Face
M25	1.5	Extra Fine	38mm	11	160°	ISO 2982-2	0000000	00000	00000000	000000

Bearing Retaining Nuts

For Chamfered Nuts

Often paired with spring lock washers to strengthen their hold, these retaining nuts—also known as shaft nuts—keep vibration from shifting bearings, bushings, pulleys, and gears on your threaded shaft or spindle. They have slotted sides, so you can tighten and loosen them with a spanner wrench or spanner socket. Made of carbon steel, they’re strong and wear resistant.

Use stepped-face retaining nuts with DIN 462 spring lock washers. You can also use them in pairs or with other bearing retaining nuts as jam nuts. For the nut closer to the bearing, position the stepped face towards the bearing. All meet DIN standards for bearing lockout dimensions.

Chamfered-face retaining nuts weigh less and produce less heat than stepped-face nuts. They meet ISO 2982 (formerly DIN 981), an international standard for bearing locknut dimensions. Their sizes correspond to SKF KM series. Use them with DIN 5406 spring lock washers.

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

Nuts
Thread									Optional Washers		Spanner Sockets
Size	Pitch, mm	Spacing	OD, mm	Wd., mm	Specifications Met	For Lock Washer Specifications Met		Each		Each		Each
Carbon Steel
Chamfered Face
M25	1.5	Extra Fine	38	7	DIN 981, ISO 2982	DIN 5406	0000000	00000	000000000	00000	00000000	0000000

Aluminum Cord Grips

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

Locknut and O-Ring Kit

These cord grips are lightweight yet durable. As you tighten the grip, a nylon inner ring and lubricated rubber bushing secure your cable, prevent overtightening, and create a seal around the cord to block out liquid. The inner rings are colored by size so you can identify them at a glance.

Locknut and O-ring kits (sold separately) create liquid-tight seals between cord grips and enclosure knockouts. Rated NEMA 4X, NEMA 13, and IP66, the resulting seals provide indoor and outdoor protection against dust, corrosion, water projected from a hose, and oil/coolant spray. Each kit includes two locknuts and one or two O-rings.

Cord Grips
		Knockout Connection					Each		Locknut and O-Ring Kits
For Cord OD	For Knockout Trade Size	Type	Gender	Temperature Range, °F	Specifications Met		1-9	10-Up		Each
Metric Threads
0.38"-0.5"	M25	Threaded	Male	-30° to 225°	UL Listed	00000000	00000	00000	00000000	00000
0.5"-0.62"	M25	Threaded	Male	-30° to 225°	UL Listed	00000000	0000	0000	00000000	0000

High-Temperature Plastic Submersible Cord Grips

Made of PVDF, these grips are able to withstand temperatures up to 300° F and are corrosion- and chemical-resistant. Grips are rated NEMA 12 for protection from splashing oil and coolant as well as IP68 and NEMA 6 for protection from continuous submersion. They’re also rated IP69K and NEMA 4X, which means in addition to being submersible, they withstand high-pressure, high-temperature washdowns and can be dunked in corrosive liquids without any affect. A rubber bushing and O-ring create a tight seal to prevent liquid from entering the connection.

Metric Threads
For Cord OD	For Knockout Trade Size	Temp. Range, °F	Features	Environmental Rating	Specifications Met		Each
0.35"-0.63"	M25	-30° to 300°	Nickel-Plated Brass Locknut, Rubber O-Ring	IP68, IP69K, NEMA 4X, NEMA 6, NEMA 12	UL Listed, CSA Certified, UL 94 V-0	0000000	000000
0.51"-0.71"	M25	-30° to 300°	Nickel-Plated Brass Locknut, Rubber O-Ring	IP68, IP69K, NEMA 4X, NEMA 6, NEMA 12	UL Listed, CSA Certified, UL 94 V-0	0000000	00000

Plastic Submersible Cord Grips

Able to resist most chemicals and withstand use underwater, these nylon grips are rated IP68 for protection from dusty environments and continuous submersion. A rubber bushing and O-ring create a tight seal to prevent liquid from entering the connection. All are CE marked and TUV Rheinland certified, which means they meet European safety standards. Grips with UL certifications meet American safety standards, while those with C-UL and CSA certifications meet Canadian safety standards. Some also meet standards for marine vessels classed by DNV-GL.

Grips with metric threads meet IP69 or IP69K for protection from high-pressure washdowns.

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

							Each
For Cord OD	For Knockout Trade Size	Temp. Range, °F	Features	Environmental Rating	Specifications Met		1-9	10-Up
Metric Threads
0.35"-0.67"	M25	0° to 175°	Nylon Plastic Locknut, Rubber O-Ring	NEMA 12, IP66, IP68, IP69	UL Listed, C-UL Listed, CSA Certified, CE Marked, DNV-GL Type Approved, TUV Rheinland Certified, VDE Certified	0000000	00000	00000

90° Elbow Plastic Submersible Cord Grips

Able to resist most chemicals and withstand use underwater, these nylon grips are rated IP68 and 69K for protection from continuous submersion and high-pressure, high-temperature jets of water. They are also rated NEMA 4X, 6, and 12 for indoor and outdoor protection against corrosion, water projected from a hose, and dripping oils and lubricants. A rubber bushing and O-ring create a tight seal to prevent liquid from entering the connection. All meet UL 746C f1, so they’re UV resistant and can be used in direct sunlight, as well as UL 94 V-0, which means they’ll self-extinguish within 10 seconds of catching fire and won’t spread flames by dripping. UL recognized, UL listed, and CSA certified, they meet U.S. and Canadian safety standards.

Metric Threads are also VDE certified, meaning they meet European safety standards.

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

Metric Threads
For Cord OD	For Knockout Trade Size	Material	Temp. Range, °F	Features	Environmental Rating	Specifications Met		Each
0.35"-0.63"	M25	Black Nylon Plastic	-20° to 210°	Nylon Plastic Locknut, Rubber O-Ring	IP68, IP69K, NEMA 4X, NEMA 6, NEMA 12	UL Recognized Component, UL Listed, UL 94 V-0, UL 746C f1, CSA Certified, VDE Certified	0000000	000000
0.51"-0.71"	M25	Black Nylon Plastic	-20° to 210°	Nylon Plastic Locknut, Rubber O-Ring	IP68, IP69K, NEMA 4X, NEMA 6, NEMA 12	UL Recognized Component, UL Listed, UL 94 V-0, UL 746C f1, CSA Certified, VDE Certified	0000000	00000

Plastic Submersible Cord Grips for Building Cable

A rubber bushing with an oval slot resists water and provides entry for building cable, which is also known as Romex type NM-B or type UF-B cable. They are rated IP68 and IP69K for protection from continuous submersion and high-pressure, high-temperature jets of water. Made of nylon, these cord grips keep electrical assemblies lightweight. They also withstand chemicals and corrosive environments.

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

For Cord
Wd.	Thick.	For Knockout Trade Size	Material	Temp. Range, °F	Features	Environmental Rating	Specifications Met		Each
Metric Threads
0.55"	0.24"	M25	Black Nylon Plastic	-40° to 210° F	Rubber O-Ring, Nylon Plastic Locknut	IP68, IP69K, NEMA 4X, NEMA 6, NEMA 12	UL 746C f1, UL 94 V-0	0000000	00000
0.55"	0.28"	M25	Black Nylon Plastic	-40° to 210° F	Rubber O-Ring, Nylon Plastic Locknut	IP68, IP69K, NEMA 4X, NEMA 6, NEMA 12	UL 746C f1, UL 94 V-0	0000000	0000

Screw-Down Sure-Grip Plastic Submersible Cord Grips

Tighten the screw-down clamp on these grips for superior pull-out resistance while relieving tension at connection points. Grips are rated IP68 for protection from continuous submersion and IP69K for protection against high-pressure, high-temperature jets of water. A rubber bushing and O-ring create a tight seal to prevent liquid from entering the connection.

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

For Cord OD	For Knockout Trade Size	Thread Type	Material	Temp. Range, °F	Features	Environmental Rating	Specifications Met		Each
0.51"-0.71"	M25	Metric	Black Nylon Plastic	0° to 155° F°	Rubber O-Ring, Nylon Plastic Locknut	IP68, IP69K, NEMA 4X, NEMA 6, NEMA 12	CSA Certified, UL Listed, UL 746C f1, UL 94 V-0	0000000	000000

Stainless Steel Submersible Cord Grips

These stainless steel grips offer the most corrosion resistance of any of our submersible metal cord grips. Grips are rated IP68 for protection from continuous submersion and IP69K for protection from high-pressure, high-temperature jets of water.. A rubber bushing and O-ring create a tight seal to prevent liquid from entering your connection.

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

Metric Threads
For Cord OD	For Knockout Trade Size	Temp. Range, °F	Features	Environmental Rating	Specifications Met		Each
0.35"-0.63"	M25	-20° to 210°	Rubber O-Ring, Nickel-Plated Brass Locknut	IP68, IP69K, NEMA 4X, NEMA 6, NEMA 12	CE Marked, CSA Certified, UL Listed	0000000	000000
0.51"-0.71"	M25	-20° to 210°	Rubber O-Ring, Nickel-Plated Brass Locknut	IP68, IP69K, NEMA 4X, NEMA 6, NEMA 12	CE Marked, CSA Certified, UL Listed	0000000	00000

Brass Submersible Cord Grips

PG and Metric Threads

Suitable for use in applications where cords are underwater—these grips are rated IP68 for protection from continuous submersion. They are nickel plated for good corrosion resistance. A rubber bushing and O-ring create a tight seal to prevent liquid from entering your connection.

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

Metric Threads
For Cord OD	For Knockout Trade Size	Thread Size	Temp. Range, °F	Features	Environmental Rating	Specifications Met		Each
0.35"-0.67"	M25	M25	0° to 210°	Nickel-Plated Brass Locknut, Rubber O-Ring	IP68, NEMA 4X, NEMA 6, NEMA 12	CE Marked, DNV-GL Type Approved, VDE Certified	0000000	000000

Wraparound Multi-Cord Grips

Attach a cord grip to cable without removing connectors and rewiring. These cord grips have a two-piece design to fit around cables with connectors. Choose a housing and then select inserts (sold separately). Inserts have a slit, eliminating the need to thread cable through them.

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

Knockout-Mount Housings

Knockout-Mount Housing

Knockout-Mount Housing Shown Open

1 Small Insert

		For Insert
For No. of Inserts	For Knockout Trade Size	Ht.	Wd.	Size	Thread Type	For Max. Panel Thick.	Temp. Range, °F	Features	Environmental Rating	Specifications Met		Each
Gray Polycarbonate Plastic
1	M25	0.83"	0.83"	Small	Metric	0.31"	-20° to 190°	Nylon Plastic Locknut, Rubber Gasket	NEMA 12, IP54	UL Recognized Component, UL 94 V-0, C-UL Recognized Component, DNV-GL Type Approved	00000000	000000

Low-Profile Submersible Break-Through Multi-Cord Grips

For 3 Cords

For 4 Cords

The face of these grips is flush with the cable-entry point for a seamless appearance. They have a thin, flexible seal that covers the holes until you push a cord through. Grips are rated IP66, IP68, NEMA 4X, and NEMA 12 for protection from continuous submersion, washdowns and oil/coolant splashing.

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

For 3 Cords
Shape	For Cord OD (No. of Cords)	For Knockout Trade Size	Thread Type	For Max. Panel Thick.	Material	Temp. Range, °F	Features	Environmental Rating	Specifications Met		Each
Straight	0.13"-0.2" (2), 0.13"-0.25" (1)	M25	Metric	0.32"	Gray Nylon Plastic	-40° to 190°	Nylon Plastic Locknut	NEMA 4X, NEMA 12, IP66, IP68	UL Recognized Component, UL 94 V-0, C-UL Recognized Component, DNV-GL Type Approved	0000000	000000
For 4 Cords
Straight	0.13"-0.2"	M25	Metric	0.32"	Gray Nylon Plastic	-40° to 190°	Nylon Plastic Locknut	NEMA 4X, NEMA 12, IP66, IP68	UL Recognized Component, UL 94 V-0, C-UL Recognized Component, DNV-GL Type Approved	0000000	00000

Metric Ball Screws and Nuts

Internal ball bearings provide smooth low-friction travel in applications that require high speeds, accurate positioning, and repeatable movement. Also known as single-start ball screws and nuts, these have a single thread that runs the length of the screw. They operate with more torque than fast-travel ball screws and nuts. To ensure compatibility, select components that have the same thread size and pitch. Ball nuts are furnished with a tube to keep ball bearings in place. Do not remove the tube until you are ready to install the nuts onto the screws.

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

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

Platform Ball Nuts—Right-Hand Threaded

Alloy Steel
Thread Size	Thread Pitch, mm	Lg., mm	Wd., mm	Ht., mm	Center Ht., mm	No. of Thread Starts	Travel Distance per Turn, mm	Hardness	Dynamic Thrust Load Cap., lbs.	Max. Backlash, mm	Temperature Range, °F		Each
M25	0.1	94	60	55	23	1	10	Rockwell C58	7,000	0.1	5° to 175°	0000000	0000000
M25	0.2	35	60	45	20	1	5	Rockwell C58	1,500	0.1	5° to 175°	0000000	000000

Flange Ball Nuts—Right-Hand Threaded

				Flange
Thread Size	Thread Pitch, mm	Lg., mm	Dia., mm	Wd., mm, mm	Ht., mm	Thick., mm	No. of Thread Starts	Travel Distance per Turn, mm	Hardness	Dynamic Thrust Load Cap., lbs.	Max. Backlash, mm	Temperature Range, °F		Each
Alloy Steel
M25	0.1	98	60	96	72	15	1	10	Rockwell C58	7,000	0.1	5° to 175°	0000000	0000000
M25	0.2	40	43	67	50	10	1	5	Rockwell C58	1,500	0.1	5° to 175°	0000000	000000

Metric Precision Ball Screws and Nuts

Precision cut threads make these metric ball screws approximately four times more accurate than standard ball screws. Use them when exact positioning is essential. They come with finished ends and the nut already on, so they’re ready to use right away. The ball nuts have a flange design that makes it easy to mount objects on them. Inside, they have ball bearings to produce smooth, low-friction travel for applications that require high-speed and repeatable movement.

Ball nuts with a thread pitch less than 1 mm have a seal that prevents some contaminants from getting inside them. However, to make sure they don’t create torque and heat, there’s a bit of clearance between the seal and screw, so the seal can’t keep out everything.

Ball nuts with end caps dampen the noise from the ball bearings and make the ball nuts more compact.

Root diameter indicates the diameter the ball screw will be after machining away the threads.

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

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

		Ball Screw		Flange Ball Nut
Thread Size	Thread Pitch, mm	Lg., mm	Root Dia., mm	Lg., mm	Dia., mm	No. of Thread Starts	Travel Distance per Turn, mm	Accuracy for Travel Distance per Turn	Hardness	Dynamic Thrust Load Cap., lbs.	Max. Backlash, mm	Includes	Temp. Range, °F		Each
Carbon Steel Ball Screw with Alloy Steel Flange Ball Nut
M25	0.05	751	21.9	53	47	2	20	±0.023 mm per 300 mm	Rockwell C58	2,350	0	End Caps	Not Rated to 175°	00000000	000000000
M25	0.05	851	21.9	53	47	2	20	±0.023 mm per 300 mm	Rockwell C58	2,350	0	End Caps	Not Rated to 175°	00000000	00000000
M25	0.05	1,051	21.9	53	47	2	20	±0.023 mm per 300 mm	Rockwell C58	2,350	0	End Caps	Not Rated to 175°	00000000	00000000
M25	0.05	1,251	21.9	53	47	2	20	±0.023 mm per 300 mm	Rockwell C58	2,350	0	End Caps	Not Rated to 175°	00000000	00000000
M25	0.05	1,451	21.9	53	47	2	20	±0.023 mm per 300 mm	Rockwell C58	2,350	0	End Caps	Not Rated to 175°	00000000	00000000
M25	0.05	1,651	21.9	53	47	2	20	±0.023 mm per 300 mm	Rockwell C58	2,350	0	End Caps	Not Rated to 175°	00000000	00000000
M25	0.05	1,851	21.9	53	47	2	20	±0.023 mm per 300 mm	Rockwell C58	2,350	0	End Caps	Not Rated to 175°	00000000	00000000

Metric Fast-Travel Ball Screws and Nuts

With multiple thread starts, these metric ball screws create linear travel that’s approximately three times faster than ball screws with a single thread start. They’re ideal for applications with an actuator. The ball nuts have internal ball bearings to produce smooth, low-friction travel for applications that require high speed, accurate positioning, and repeatable movement. They come with a tube to keep the ball bearings in place. Do not remove the tube until you’re ready to install the nuts onto the screws. All of these ball nuts have an end cap on each end to stabilize fast-rotating motion. End caps also dampen the noise from the ball bearings and make the ball nuts more compact. Seals on the ball nuts keep out dust.

To ensure compatibility, select components that have the same thread size and pitch.

Ball nuts with four mounting holes have a lower profile than ball nuts with six mounting holes, so they’re better when assembly height clearance is tight.

Ball nuts with six mounting holes have a support bearing for greater axial rigidity than ball nuts with four mounting holes. They’re responsive to motor and actuator movements.

Root diameter indicates the diameter the ball screw will be after machining away the threads.

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

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

Ball Screws—Right-Hand Threaded

Carbon Steel
Thread Size	Thread Pitch, mm	Lg., mm	No. of Thread Starts	Travel Distance per Turn, mm	Accuracy for Travel Distance per Turn	Root Dia., mm	Hardness	Temp. Range, °F		Each
M25	0.04	500	4	25	±0.210 mm per 300 mm	21.9	Rockwell C58	Not Rated to 175°	00000000	0000000
M25	0.04	1,000	4	25	±0.210 mm per 300 mm	21.9	Rockwell C58	Not Rated to 175°	0000000	000000
M25	0.04	1,500	4	25	±0.210 mm per 300 mm	21.9	Rockwell C58	Not Rated to 175°	00000000	000000
M25	0.04	2,000	4	25	±0.210 mm per 300 mm	21.9	Rockwell C58	Not Rated to 175°	00000000	000000
M25	0.04	2,500	4	25	±0.210 mm per 300 mm	21.9	Rockwell C58	Not Rated to 175°	00000000	000000
M25	0.04	3,000	4	25	±0.210 mm per 300 mm	21.9	Rockwell C58	Not Rated to 175°	00000000	000000

Style A Flange Ball Nuts—Right-Hand Threaded

				Flange
Thread Size	Thread Pitch, mm	Lg., mm	Dia., mm	Wd., mm	Ht., mm	Thick., mm	No. of Thread Starts	Travel Distance per Turn, mm	No. of Mounting Holes	Hardness	Dynamic Thrust Load Cap., lbs.	Max. Backlash, mm	Includes	Temp. Range, °F		Each
Alloy Steel
M25	0.04	55	47	74	56	12	4	25	4	Rockwell C58	2,710	0.1	End Caps Seals	Not Rated to 175°	00000000	0000000
M25	0.04	55	47	74	56	12	4	25	4	Rockwell C58	4,920	0.1	End Caps Seals	Not Rated to 175°	00000000	000000

Style B Flange Ball Nuts—Right-Hand Threaded

				Flange
Thread Size	Thread Pitch, mm	Lg., mm	Dia., mm	Dia., mm	Thick., mm	No. of Thread Starts	Travel Distance per Turn, mm	No. of Mounting Holes	Bolt Circle Dia., mm	Hardness	Dynamic Thrust Load Cap., lbs.	Max. Backlash, mm	Includes	Temp. Range, °F		Each
Alloy Steel
M25	0.04	65	72	92	8	4	25	6	81	Rockwell C58	2,710	0.1	End Caps Seals	Not Rated to 175°	0000000	0000000

About Shaft Collars

Selecting Compatible Lead Screws and Nuts

About Washers

Bearing Retaining Locknuts

Bearing Retaining Nuts

Aluminum Cord Grips

High-Temperature Plastic Submersible Cord Grips

Plastic Submersible Cord Grips

90° Elbow Plastic Submersible Cord Grips

Plastic Submersible Cord Grips for Building Cable

Screw-Down Sure-Grip Plastic Submersible Cord Grips

Stainless Steel Submersible Cord Grips

Brass Submersible Cord Grips

Wraparound Multi-Cord Grips

Low-Profile Submersible Break-Through Multi-Cord Grips

Metric Ball Screws and Nuts

Metric Precision Ball Screws and Nuts

Metric Fast-Travel Ball Screws and Nuts