5/16"-24 Adapters | McMaster-Carr

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336 Products

Pipe, Tubing, Hose, and Fittings

Extreme-Pressure Stainless
Steel Threaded Pipe Fittings

Use these fittings in extreme-pressure conditions up to 15,000 psi.

Straight-Flow Rectangular Manifolds

Unlike other manifolds, which have an inlet on either end, these have one inlet on the opposite side from the outlets. This design allows air or fluid to follow a straight path, improving flow through your system. Also known as headers.

Low-Profile Square Manifolds

With outlets on the side instead of on top, these manifolds have a lower profile than rectangular manifolds and fit well in cramped spaces. Use them to distribute air or fluid to three locations from a single supply source.

37° Flared Fittings for Stainless Steel Tubing

Also known as JIC (Joint Industrial Council) fittings, these provide a tight metal-to-metal seal on stainless steel tubing that is flared to 37°.

37° Flared Fittings with Thread
Sealant for Stainless Steel Tubing

The male pipe threads on these fittings have a sealant applied for extra protection against leaks.

Precision AN 37° Flared Fittings
for Stainless Steel Tubing

The threads on the tube end of these fittings are Class 3A or 3B and adhere to tighter tolerances than other 37° flared fittings.

Yor-Lok Fittings for Stainless Steel Tubing

Use these fittings at pressures up to 9,700 psi. Also known as instrumentation fittings, they are made to tight tolerances for use in high-precision applications. They are compatible with Swagelok®, Let-Lok, and Parker A-Lok fittings.

45° Flared Fittings for Copper and Brass Tubing

No sleeve is required to assemble these fittings, which makes for a faster, more convenient installation compared to 37° flared fittings. They are also known as refrigeration and SAE fittings.

37° Flared Fittings for Copper Tubing

Also known as JIC (Joint Industrial Council) fittings, these connect to tubing that is flared to 37°. They can handle higher pressures than 45° flared fittings.

37° Flared Fittings for Steel Tubing

Also known as JIC (Joint Industrial Council) fittings, these provide a tight metal-to-metal seal on steel tubing that is flared to 37°.

Thread Adapters

Inch-to-Inch Male-Female Hex Thread Adapters

Change thread sizes or types, such as fine to coarse threads, on parts without changing gender.

Inch-to-Metric Male-Female Hex Thread Adapters

Change inch threads to metric with these adapters, or swap metric threads for inch. An external hex lets you tighten or loosen them with a wrench.

Inch-to-Inch Male Hex Thread Adapters

Need to join two female-threaded parts, such as coupling nuts, with dissimilar inch thread sizes? Attach them to these adapters and tighten the exterior hex nut for a secure connection.

Inch-to-Metric Male Hex Thread Adapters

One side inch, one side metric, and a hex in the middle—these handy fasteners connect two female-threaded parts, such as coupling nuts, adapting from inch threads to metric. Tighten with a standard wrench.

Inch-to-Inch Female Hex Thread Adapters

Connect two differently sized male-threaded parts, such as threaded rods, and tighten with a standard wrench.

Inch-to-Metric Female Hex Thread Adapters

Adapt threaded rods from inch to metric. These adapters connect two male-threaded fasteners, so you can change the gender of a mating part or increase or decrease its thread size. The hex-shaped body fits into the head of a standard wrench.

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.

Threaded Inserts for Metal

18-8 Stainless Steel Easy-to-Install
Thread-Locking Inserts

Made of 18-8 stainless steel, these inserts have better corrosion resistance than black-phosphate steel.

Black-Phosphate Steel Easy-to-Install
Thread-Locking Inserts

A black-phosphate finish provides mild corrosion resistance.

Easy-to-Install Thread-Locking Insert Assortments

These assortments include various sizes of thread-locking inserts.

18-8 Stainless Steel Key-Locking Inserts

Made of 18-8 stainless steel, these inserts have good corrosion resistance.

Black-Phosphate Steel Key-Locking Inserts

A black-phosphate finish provides mild corrosion resistance.

Mil. Spec. Stainless Steel Key-Locking Inserts

These inserts are made to stringent military specifications.

Mil. Spec. Alloy Steel Key-Locking Inserts

The strongest key-locking inserts we offer, these inserts are made to stringent military specifications.

Key-Locking Insert Assortments with Installation Tool

Screw-Locking Key-Locking Inserts

Forming the strongest hold of any of our threaded inserts, these inserts have a distorted internal thread to lock screws into place and keys that drive into surrounding material to prevent slipping and rotating.

Key-Locking Inserts with Installation Tool

These inserts come with an installation tool. Drive the keys into the surrounding material for a more secure hold than thread-locking inserts.

Nuts

Steel Hex Weld Nuts

Weld these nuts to flat and uneven uncoated steel surfaces for a strong permanent hold.

Square Weld Nuts

Square weld nuts have more weld points than hex weld nuts for a stronger hold. Use them on flat surfaces.

Stainless Steel Low-Profile
Narrow-Base Weld Nuts with Projections

Projections on the base concentrate the weld and create space for heat to dissipate, protecting the threads on these weld nuts from deforming. Made of 18-8 stainless steel, they withstand mild chemicals and can be used in wet and outdoor environments.

Steel Low-Profile Narrow-Base
Weld Nuts with Projections

Projections on the base concentrate the weld and create space for heat to dissipate, protecting the threads on these steel weld nuts from deforming.

Stainless Steel Offset-Barrel Narrow-Base Weld Nuts

Weld these nuts to stainless steel surfaces.

Steel Offset-Barrel Narrow-Base Weld Nuts

An offset barrel allows you to position threads near edges and corners.

Aligning Weld Nuts

Threads float inside the retainer so you can install a bolt at a slight angle to align with off center parts.

Tube-End Weld Nuts

Weld these nuts to round uncoated metal tubes to attach threaded parts, such as rod ends.

Left-Hand Threaded Tube-End Weld Nuts

Use these tube-end weld nuts with left-hand threaded fasteners.

Hex Drive Threaded Rods

A hex drive on one end allows these rods to be turned with a hex key for ease of installation.

Forcing Screws for Pullers

Make your old puller work like new by replacing worn forcing screws.

Backup Pads for Sanding Discs

Backup Pads with Threaded Stud
for Hook and Loop Sanding Discs

Thread the stud into the tool's spindle.

Backup Pads with Threaded Stud for Nylon
Mesh Cushioned Hook and Loop Sanding Discs

Vacuum Sanding Backup Pads with Threaded
Stud for Hook and Loop Sanding Discs

Holes allow dust removal when used with a vacuum sander.

Backup Pads with Threaded Stud
for Adhesive-Back Sanding Discs

Thread the stud into the tool's spindle and then press the sanding disc onto the backup pad.

Vacuum Sanding Backup Pads with Threaded
Stud for Adhesive-Back Sanding Discs