3 3/4" Hex Drivers | 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.

Black-Oxide Steel—The dark, matte coating protects these wrenches from wear and won't flake off. They offer minimal corrosion resistance, though, so they're best for dry environments.

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	Overall Lg.	Head Offset Angle	Head Thick.	Opening Angle	Head Thick.	Appearance		Each
12-Point Opening







				Black-Oxide Steel

				3 3/4"	40"	15°	2 1/4"	15°	1 1/2"	Dull	7242A68	000000000

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	Nut	Bolt	Compatible Retaining Ring ID	Material	Overall Lg.	Socket Shape		Each		Each
1" Square Drive



		3 3/4"	2 1/2"	3 29/32"	3 1/8"	Black-Oxide Steel	5"	6-Point	5550A172	0000000	5550A156	00000

Deep Clearance


		6-Point Socket

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



		3 3/4"	2 1/2"	4 3/4"	3 1/8"	Black-Oxide Steel	6 1/4"	6-Point	5550A765	0000000	5550A156	00000

Deep-Offset Striking Box Wrenches

The head is offset 45° to provide clearance for reaching over obstructions. Also known as slugging wrenches, strike the handle with a hammer to break stuck fasteners free.

	Overall Lg.	Head Offset Angle	Head Thk.	Material	Specs. Met		Each
12-Point Opening



	3 3/4"	18"	45°	2 3/8"	Black-Oxide Steel	ASME B107.100	5455A63	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-Oxide Steel—The dark, matte coating protects these wrenches from wear and won't flake off. They offer minimal corrosion resistance, though, so they're best for dry environments.

	Head Thk.	Specs. Met		Each
Round Opening







	Black-Oxide Steel

	3 3/4"	37"	15°	1 3/4"	ASME B107.100	5400A66	0000000

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

	3 3/4"	17 1/2"	15°	1 1/2"	DIN 133	55555A58	0000000

Striking Box Wrenches

12-Point Opening

Also known as slugging wrenches, strike the handle with a hammer to break stuck fasteners free.

12-Point Opening—Wrenches with a 12-point opening are easier to position on hex fasteners than wrenches with a 6-point opening but make less contact.

	Overall Lg.	Head Thk.	Material	Specs. Met		Each
12-Point Opening



	3 3/4"	14 1/2"	1 23/32"	Black-Oxide Steel	ASME B107.100	5456A36	0000000