5/8"-18 Fasteners | McMaster-Carr

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System of Measurement

Thread Size

Length

Material

Threading

Threaded on Both Ends

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Fastener Head Type

Finish

Cadmium Yellow-Chromate Plated

Zinc Yellow-Chromate Plated

Thread Spacing

Thread Direction

Right Hand and Left Hand

Thread Type

Metric

Metric Rounded Trapezoidal

Nut Type

Drive Style

Tensile Strength

30,000 psi to 99,999 psi

100,000 psi or greater

Not Rated

Thread Fit

Metric Class 6H

Unified Standard Class 1A

Unified Standard Class 2A

Unified Standard Class 2B

Unified Standard Class 3A

Unified Standard Class 3B

Specifications Met

Performance

DFARS Specialty Metals

Compliant

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Not Compliant

U.S.–Mexico–Canada Agreement (USMCA) Qualifying

REACH

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Compliant with Exemptions

Not Compliant

Export Control Classification Number (ECCN)

Head Height

Thread Pitch

Thread Length

632 Products

Fastening and Joining

Hex Head Screws

Used with nuts to create a stronger joint than flat and rounded screws

133 products

Socket Head Screws

With a deeper drive than flat and rounded head screws, these withstand more torque for a tighter hold

34 products

Shoulder Screws

Rotate parts around the cylinder under the head to guide and align them during installation

24 products

Set Screws

Exert pressure at the tip to hold parts in place, unlike screws that hold material together with threads

33 products

Flat Head Screws

Fit in countersunk holes for a flush finish that won't snag on surrounding parts

14 products

Rounded Head Screws

Sit just above the surface for a low-profile finish and hold tighter than flat head screws

3 products

12-Point Screws

12 contact points handle more torque than a hex head while a flange eliminates the need for a washer

2 products

Locknuts

Hold fasteners in place to prevent loosening from vibration

38 products

Hex Nuts

Handle most general fastening needs

55 products

Coupling Nuts

Connect and extend threaded rods

14 products

Flange Nuts

The flange distributes pressure, so you don't need a washer

15 products

Socket Nuts

Install in recessed holes and tight spots where a wrench won’t fit; also known as Allen nuts

1 product

Cap Nuts

Cover and protect threads while adding a finished look; also known as acorn nuts

5 products

Sealing Nuts

Prevent leaks and block out contaminants with a rubber seal

1 product

Thumb Nuts

Easy to tighten and loosen by hand for making frequent adjustments

1 product

Tamper-Resistant Nuts

Hard to detach without special tools to prevent unwanted removal

3 products

Threaded Inserts

Create new threads or repair stripped threads

46 products

Weld Nuts

Weld to metal surfaces to add permanent threads

26 products

Threaded Rods

Anchor, connect, or hang components in a wide variety of applications

77 products

Thread Adapters

Join threads of a different type, size, and gender

11 products

Taper Pins

Fit snugly into tapered holes to secure, position, and align components

12 products

Threaded Insert Installation Tools

Install helical, key-locking, slotted-drive, and other threaded inserts

14 products

Fabricating and Machining

Toggle Clamps

Lock workpieces onto worktables or objects

5 products

Drill Bushings

Fit in holes to guide drill bits and other cutting tools for precise and repeatable holes and cuts

11 products

Fluid Handling

Hose Nuts

Connect fittings and compressed-gas nipples to pressure regulators and torches

3 products

Tube Fitting Nuts

Tighten to create a strong seal between tube and tube fittings

4 products

Power Transmission

Connecting Rods

Use with rod ends and swivel joints to link components in push/pull assemblies

33 products

Precision Lead Screw Nuts

Pair with precision lead screws for accurate starts and stops in your assembly

2 products

Material Handling

Eyebolts

Route rope through the loop or attach hooks and shackles for lifting

4 products

Turnbuckles

Twist the body or end fittings to adjust the length and tension of attached rope and chain

14 products

Building and Machinery Hardware

Handle Nuts

Attach to threaded shafts to quickly turn the shafts by hand

2 products