5/16"-18 Adapters | McMaster-Carr

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Adhesive-Mount Nuts

Battery Terminal Adapters

Battery Terminal Fasteners

Flexible Shaft Couplings

Leveling Mount Inserts

Pipe Threader Dies

Robot Workstations

Rod Ends

Slide Hammer Adapters for Locking Pliers

System of Measurement

Thread Size

Material

Hex Length

Gender

Thread Length

Hex Size

Length

For Adapting

Shape

Finish

Thread Type

UN/UNF (SAE Straight)

Thread Fit

Unified Standard Class 1A

Unified Standard Class 1B

Unified Standard Class 2A

Unified Standard Class 2B

Unified Standard Class 3A

Unified Standard Class 3B

Drive Style

Pipe Size

Fitting Type

Tensile Strength

40,000 psi to 49,999 psi

50,000 psi to 59,999 psi

60,000 psi to 99,999 psi

100,000 psi or greater

Not Rated

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

REACH

RoHS

Compliant with Exemptions

Not Compliant

Export Control Classification Number (ECCN)

EAR99

DFARS Specialty Metals

Pitch

Hardness

Specifications Met

Screw Size

608 Products

Thread Adapters

Male-Female Thread Adapters

Inch-to-Inch Male-Female Hex Thread Adapters

Change thread size and spacing

87 products

Inch-to-Metric Male-Female Hex Thread Adapters

Change inch threads to metric

80 products

Inch-to-NPT Male-Female Hex Thread Adapters with Through Hole

Connect float rods to float valves with the through hole

4 products

Male Thread Adapters

Inch-to-Inch Male Hex Thread Adapters

Join two female-threaded parts with dissimilar inch thread sizes

50 products

Inch-to-Metric Male Hex Thread Adapters

Join inch and metric female-threaded parts

39 products

Left-Hand to Right-Hand Male Thread Adapters

Fasten parts with right-hand threads to parts with left-hand threads

4 products

Female Thread Adapters

Inch-to-Inch Female Hex Thread Adapters

Join two male-threaded parts with dissimilar inch thread sizes

47 products

Inch-to-Metric Female Hex Thread Adapters

Join two male-threaded parts with inch and metric thread sizes

44 products

Left-Hand to Right-Hand Female Hex Thread Adapters

Join two male-threaded parts with dissimilar metric thread sizes
Fasten parts with right-hand threads to parts with left-hand threads

3 products

Thread Adapters for Pullers

Pair with an external grip puller to pull shafts, bearing caps, and pinions

1 product

Hex Drive Thread Adapters

Join coarse threads to fine threads using a hex key

4 products

Other Products

Threaded Inserts

Create new threads or repair stripped threads

100 products

Tube Straights

Join lengths of tube to send contents in one direction

5 products

Adhesive-Mount Nuts

Attach threads to material that’s too thin for a threaded insert

10 products

Tube-Connecting Nuts

Push inside tubes to join them with a threaded stud instead of welding

7 products

Battery Terminal Adapters

Convert one battery terminal style to another

2 products

Studs

Press, weld, or screw in place to add a threaded fastening point

14 products

Battery Terminal Fasteners

Replace bolts in battery terminals

2 products

Slide Hammer Adapters for Locking Pliers

Attach your locking pliers to a slide hammer to pull stubborn objects

1 product

Rod Ends

Use with connecting rods to support loads and control steering, tensioning, or pivoting motion

46 products

Weld Nuts

Weld to metal surfaces to add permanent threads

40 products

Leveling Mount Inserts

Slip onto equipment and furniture to add threaded-stud leveling feet

6 products

Flexible Shaft Coupling Hubs

Pair with spiders, discs, or grids for a complete flexible shaft coupling

4 products

U-Joints

Transfer torque between shafts at an angle; handle more torque and misalignment than flexible shafts

2 products

Pipe Threader Dies

Install in the die head on your Ridgid pipe threader to cut external pipe and conduit threads

1 product

Robot Workstations

Create a portable working home for your robot arm

5 products