55 mm Wrenches | McMaster-Carr

Your go-to wrenches for routine maintenance. With two different ends, you need fewer tools to tighten and loosen nuts and bolts. The open end slides onto the side of fasteners for adjustments in tight spots. When nuts and bolts won't budge, the box end fully encircles them to apply maximum torque. Drop forged for added strength, these wrenches will be part of your toolbox for life.

12-Point Opening—The most common opening, these wrenches work on hex and 12-point nuts and bolts. They slide onto hex heads at more angles than 6-point fasteners for quicker engagement, but they're more likely to slip when you apply more torque.

Chrome-Plated Steel—The most popular finish, these wrenches won't rust or chip. Although they withstand moisture better than black oxide, they don't hold up to harsh chemicals as well as stainless steel.

Dull—With a textured finish, these wrenches won't slip out of your hands, even when greasy or oily.

			Box End		Open End
	Drive Size, mm	Overall Lg.	Head Offset Angle	Head Thick.	Opening Angle	Head Thick.	Appearance	Specs. Met		Each
12-Point Opening







				Chrome-Plated Steel

				55	29"	15°	1 37/64"	15°	63/64"	Dull	ASME B107.100	7191A82	0000000

Open-End Wrenches

Round

Opening

Adjust fasteners in tight spots such as motor housings, HVAC systems, and under sinks when you can't get a grip from the top. Slip around nuts and bolts from the side, unlike box wrenches that require more space to fit over fasteners. These wrenches are ASME or DIN certified—they handle more torque than run-of-the-mill alternatives and precisely fit fasteners so they don't round them off. Drop forged for added strength, they will be part of your toolbox for life.

Round Opening—The rounded edges spread force evenly to prevent stripping your fasteners. Use them on hex-head fasteners.

Black Phosphate-Coated Steel—The dark coating on these wrenches forms a rust-resistant barrier, making them good for wet areas. However, they won't hold up to salt water and chemicals. The coating is textured for a firm grip, even when your hands are greasy.

	Head Thk.	Specs. Met		Each
Round Opening







	Black Phosphate-Coated Steel

	55	17 1/2"	15°	21/32"	DIN 894	5488A37	000000

Tight-Clearance Open-End Wrenches

Round

Opening

Twist thin fasteners in cramped spots where other wrenches are too bulky. With a head and handle about half as thick as standard wrenches, it's easier to grip nuts found in electrical enclosures and small machinery. These wrenches are ASME certified—they handle more torque than run-of-the-mill alternatives and precisely fit fasteners so they don't round them off. Drop forged for added strength, they will be part of your toolbox for life. Also known as check nut or service wrenches.

Round Opening—The rounded edges spread force evenly to prevent stripping your fasteners. Use them on hex-head fasteners.

Dull—With a textured finish, these wrenches won't slip out of your hands, even when greasy or oily.

	Head Thk.	Appearance	Specs. Met		Each
Round Opening







	Chrome-Plated Steel

	55	9 1/2"	30°	5/16"	Dull	ASME B107.100	5746A15	000000

Strikable Open-End Wrenches

Round

Opening

Don't wrestle with stuck fasteners. Strike the handle with a hammer to break them free. Designed to take the hits, these wrenches are drop forged for added strength and will be part of your toolbox for life. Also known as slugging wrenches.

Round Opening—The rounded edges spread force evenly to prevent stripping your fasteners. Use them on hex-head fasteners.

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

	Head Thk.	Specs. Met		Each
Round Opening







	Steel

	55	11 7/8"	15°	29/32"	DIN 133	6973A27	0000000

Wheel Bearing Locknut Socket Sets

Shaped and sized for compatibility with wheel bearing locknuts on trucks and trailers, the sockets in these sets make it easy to install and remove locknuts. They ensure the proper torque setting when you reinstall a locknut on your wheel, so you know it's safe and secure. These are square drive sockets for use with hand-driven tools, not impact wrenches. Made of steel, they grip locknuts tightly and prevent rounding.

Sockets—Chrome-Plated Steel

Plastic Case

6-Point

Rounded

6-Point Rounded: 2 3/8", 2 1/2", 2 9/16", 2 3/4"—6-point rounded sockets fit the special rounded hex nuts found on some trucks.

Plastic Case—Carry sets with a plastic case from one location to the next.

6-Point Socket—6-point sockets are designed for use with hex locknuts.

	Components Included	Includes	Container Type	Socket Shape	Drive Size		Each
1/2" Square Drive



	7	7 Sockets	6-Point: 2 3/8", 2 1/2", 55 mm 6-Point Rounded: 2 3/8", 2 1/2", 2 9/16", 2 3/4",	Plastic Case	6-Point	2 3/8", 2 1/2", 2 9/16", 2 3/4", 55 mm	99939A140	0000000

6-Point Impact Sockets

Achieve the best possible grip on hex fasteners and prevent rounding. These sockets are made to withstand the high torque and force of impact tools.

Standard Clearance


		6-Point Socket

1" Square Drive—_3/4", 1", and 1 _1/2" square drive size sockets require a locking retainer. Use with an impact wrench that has a pin-style socket retainer, or use a socket retaining ring with tools that have a hole- or hole-and-ring style socket retainer.

	Sockets									Retaining Rings
		Clearance Dp.
	Drive Size, mm	Nut	Bolt	Compatible Retaining Ring ID	Material	Overall Lg.	Socket Shape		Each		Each
1" Square Drive



		55	1 21/64"	2 3/32"	2 1/4"	Black-Oxide Steel	3 3/16"	6-Point	54155A982	000000	5550A138	00000

Deep Clearance


		6-Point Socket

	Sockets									Retaining Rings
		Clearance Dp.
	Drive Size, mm	Nut	Bolt	Compatible Retaining Ring ID	Material	Overall Lg.	Socket Shape		Each		Each
1" Square Drive



		55	1 21/64"	3"	2 1/4"	Black-Oxide Steel	4 1/2"	6-Point	54155A95	0000000	5550A138	00000

6-Point Sockets

The hex shape achieves the best possible grip on hex fasteners to prevent rounding their points. For use with hand-drive tools only.

Chrome-Plated Steel


Deep Clearance	6-Point Socket

						Deep Clearance
	Drive Size, mm	OD	Specs. Met	Socket Shape	For Drive Style	Overall Lg.		Each
3/4" Square Drive



		55	2 29/32"	ASME B107.110	6-Point	External Hex	3 7/8"	5547A719	000000

12-Point Socket Sets

Made in the U.S.A., these tools handle the toughest industrial applications, provide the best grip on fasteners, and have a superior finish. The 12-point shape quickly positions on hex fasteners.

Sockets—Chrome-Plated Steel


	12-Point Socket

	Components Included	Includes	Container Type	Socket Shape	Drive Size, mm		Each
3/4" Square Drive



	13	13 Sockets	Standard: 19 mm, 20 mm, 22 mm, 24 mm, 27 mm, 30 mm, 32 mm, 36 mm, 41 mm, 46 mm, 50 mm, 55 mm, 60 mm	Metal Clip Rail	12-Point	19, 20, 22, 24, 27, 30, 32, 36, 41, 46, 50, 55, 60	8362A11	0000000

Socket Organizers

		Each
Foam Socket Organizer for 22 Piece 3/4" Square Drive Size Set	5243A22	0000000

Sockets with Drive Tools—Chrome-Plated Steel


	12-Point Socket

	Components Included	Includes	Container Type	Socket Shape	Drive Size, mm		Each
3/4" Square Drive



	30	24 Sockets 2 Drive Tools 3 Extensions Universal Joint	Standard: 19 mm, 21 mm, 22 mm, 23 mm, 24 mm, 25 mm, 26 mm, 27 mm, 28 mm, 29 mm, 30 mm, 31 mm, 32 mm, 35 mm; 36 mm, 38 mm, 41 mm Standard (cont.): 42 mm, 46 mm, 50 mm, 54 mm, 55 mm, 58 mm, 60 mm 17 1/2" Long Sliding-Head Wrench Handle 24" Long Ratchet Wrench 3 1/2" Long Extension 8" Long Extension, 16" Long Extension	Metal Case	12-Point	19, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 35, 36, 38, 41, 42, 46, 50, 54, 55, 58, 60	7874N112	000000000

Socket Organizers

		Each
Foam Socket Organizer for 22 Piece 3/4" Square Drive Size Set	5243A22	0000000

12-Point Sockets

The 12-point shape quickly positions on hex fasteners. These sockets are for hand-driven use only.

Chrome-Plated Steel


Standard Clearance	12-Point Socket

					Standard Clearance
	Drive Size, mm	OD	Socket Shape	For Drive Style	Overall Lg.		Each
3/4" Square Drive



		55	2 55/64"	12-Point	External 12-Point, External Hex	3 3/16"	7312A44	000000


		1" Square Drive



				55	3"	12-Point	External 12-Point, External Hex	3 1/4"	1788N18	000000

Economy 6-Point Socket Sets

Suitable for occasional maintenance work, these sets are imported. The hex shape grips hex fasteners and prevents rounding.

Sockets—Chrome-Plated Steel


Metal Clip Rail	6-Point Socket

	Components Included	Includes	Container Type	Socket Shape	Drive Size, mm		Each
3/4" Square Drive



	15	15 Sockets	Deep: 19 mm, 22 mm, 23 mm, 24 mm, 27 mm, 30 mm, 32 mm, 35 mm, 36 mm, 38 mm, 41 mm, 46 mm, 50 mm, 55 mm, 60 mm	Metal Clip Rail	6-Point	19, 22, 23, 24, 27, 30, 32, 35, 36, 38, 41, 46, 50, 55, 60	5894A209	0000000

Impact Hex Bit Sockets


	For Hex Drives

These sockets are made to withstand the high torque and force of impact tools.

Compatible Retaining Ring ID—Sockets that list a compatible retaining ring ID require a locking retainer. Use with an impact wrench that has a pin-style socket retainer, or use a socket retaining ring with tools that have a hole- or hole-and-ring style socket retainer.

	Bit Sockets								Retaining Rings
	Drive Size, mm	Overall Lg.	Compatible Retaining Ring ID	Material	Bit Replaceable	For Drive Style		Each		Each
1 1/2" Square Drive



		55	4 3/4"	2 7/8"	Black Oil-Coated Steel	No	Hex	54615A95	0000000	7196A75	00000