Steel Square-Head Plugs | McMaster-Carr

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Material

Drive Style

Tamper-Resistant Torx

System of Measurement

Pipe Size

Thread Type

UN/UNF (SAE Straight)

Fitting Type

Pipe Material

For Use With

Alcohol-Based Solvents

Thread Size

Gender

Body Shape

Maximum Pressure @ Temperature

Flange Material

Length

Drive Size

Shape

Pressure Class

Pipe Schedule

Plug Construction

Finish

Corrosion-Resistant Coated

Dry Film Lubricated

Galvanized

Molybdenum Disulfide Coated

Zinc Phosphate Coated

Fitting Connection

Specifications Met

Federal Specification

RoHS

Compliant with Exemptions

Not Compliant

DFARS Specialty Metals

Compliant

Exempt

Not Compliant

Export Control Classification Number (ECCN)

REACH

8,578 Products

Fluid Handling

Pipe Plugs

Insert into the ends of pipe to keep out dirt and debris

1,011 products

Pipe Caps

Cover the ends of pipe to keep out dirt and debris

303 products

Pipe Flanges

Create an access point in a line by bolting two same-size flanges together with a gasket

143 products

Pipe Fittings

Form threaded, barbed, flanged, and other types of connections between lengths of pipe

4 products

Tube End Plugs

Insert into the ends of tube to keep out dirt and debris

82 products

Tube End Caps

Cover the ends of tube to keep out dirt and debris

253 products

Tube Fittings

Make threaded, push to connect, barbed, and other types of connections between lengths of tube

21 products

Hose Fittings

Create threaded, barbed, quick-disconnect, and other types of connections between lengths of hose

565 products

Hose End Caps

Cover the ends of hose to keep out dirt and debris

23 products

Hose

Flexible and stronger than tubing; often used to convey liquids and gases under pressure

18 products

Pressure Test Fittings

Create a temporary connection point for gauges and other testing equipment

26 products

Breather Vents

Maintain even pressure and vacuum as temperatures change by allowing airflow in tanks and enclosures

1 product

Sights

Observe and monitor the contents of pipes, tanks, and other containers

116 products

Bore Sealing Plug Installation Tools

Set sealing plugs into unthreaded holes in pneumatic and hydraulic components

18 products

Building and Machinery Hardware

Protective Plugs

Insert into holes in pipe, containers, panels, and parts to keep out debris

137 products

Protective Caps

Protect just about anything, including pipe, flanges, screws, and posts

42 products

Countertop Trash Chutes

Finish the hole over a waste container

8 products

Grommets

Protect wire, cable, and cords from holes with sharp or rough edges

32 products

Strut Channel Framing and Fittings

Secure fittings in the U-shaped channel to route conduit and pipe or build other structures

28 products

Electrical

Electrical Enclosure Plugs

Block or seal holes in outlet boxes and enclosures to keep out debris, dust, and moisture

39 products

Electrical Enclosure Drains

Release moisture to keep components dry

2 products

Cord Grips

Securely connect cords to enclosures while sealing out dirt and moisture

131 products

Outlet Boxes

House electrical components such as on-off switches, receptacles, and dimmer knobs

32 products

Cable Entry Panels

Pass multiple cords into an enclosure while sealing out moisture, dust, and other contaminants

14 products

Wire and Cable Crimpers

Crimp connectors onto electrical wire or cable

57 products

Outlet Strips

Plug in multiple devices to power them from a single outlet

34 products

Electrical Connector Caps

Protect data connectors when not in use

10 products

Wall Plates

Cover switches and outlets for a finished look or to close them off when not in use

38 products

Wire Stripper Crimpers

Strip wire and crimp connectors with one tool

12 products

Electrical Contact Installation Tools

Add or remove pin-and-sleeve contacts in connectors

8 products

Wire and Cable Crimper Dies

Attach to cordless crimpers to secure connectors onto cable

63 products

Battery Chargers

Charge everything from large-cell to cordless tool to household batteries

1 product

Fastening and Joining

Socket Head Screws

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

351 products

Rounded Head Screws

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

261 products

Hex Head Screws

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

89 products

Flat Head Screws

Fit in countersunk holes for a flush finish

228 products

Tapping Screws

Fasten a range of materials together without needing to tap the hole first

134 products

Wood Screws

Fasten material to wood or pieces of wood to each other

4 products

Quick-Release Pin Receptacles

Secure quick-release pins when you don’t have a through hole

35 products

Quick-Release Pin Retaining Caps

Hold quick-release pins in holes that are oversized or out of round

23 products

Threaded Inserts

Create new threads or repair stripped threads

2,345 products

Press-Fit Nuts

Push into drilled or punched holes to add threads to thin panels

2 products

Standoff Caps

Create a finished look on standoffs and protect them from dirt and debris

2 products

Retaining Rings

Hold components on a shaft

13 products

Rivets

Join materials together permanently, especially when too thin or fragile to fasten with screws

3 products

Fabric Snaps

Join soft, heavy fabrics such as leather and canvas

22 products

Lubricating

Grease Fittings

Create an inlet on equipment and machinery for injecting lubricant; also known as Zerk fittings

332 products

Grease Fitting Adapters

Mate grease fittings when the sizes and thread types don't match

29 products

Grease Fitting Cleaning Tools

Flush out old grease, dirt, and debris from clogged fittings

2 products

Grease Fitting Repair Tools

Remove and repair broken or clogged grease fittings and re-tap threaded holes

2 products

Grease Fitting Junction Blocks

Send different types and amounts of grease from multiple grease fittings to lubricate several points

9 products

Grease Fitting Installation Tools

Tap to insert grease fittings in unthreaded holes

2 products

Oil Fittings

Install in engine blocks and other machinery to pour in oil while keeping dust out

28 products

Fabricating and Machining

Fixture Plate Plugs

Keep chips and shavings from clogging or damaging unused holes on fixture plates in milling machines

1 product

Measuring and Inspecting

Hose Coupling Size-Identification Kits

Match your hose coupling to one of the plugs to determine its size without measuring

1 product

Threaded Hole Location Gauges

Pinpoint the true center of threaded holes to precisely align and measure parts

70 products

Containers, Storage, and Furniture

Drum Plugs

Seal drum lid openings

9 products

Stacking Caps and Targets

Turn the ends of posts into stackable shelving and rack systems

6 products

Facility and Grounds Maintenance

Faucet Hole Covers

Close off unused faucet holes intended for soap dispensers and side sprayers

1 product

Sink Drain Strainers

Catch debris to prevent clogs and plug drains to fill sinks

6 products

Sink Drains

Empty liquids from sinks into sewer lines

9 products

Sealing

Tube Fitting Gaskets

Prevent leaks when connecting sanitary tube fittings

6 products