Test Plugs | McMaster-Carr

	For Pipe Size For Pipe Size

	Expansion Plug Type Expansion Plug Type


Wing Nut	Inflatable

Hex Nut	T-Handle

Snap	Square Head

	Sealing Location Sealing Location


End of Pipe	Inside Pipe	End of Tube

	For Minimum Pipe ID For Minimum Pipe ID

	Plate Material Plate Material

Stainless Steel

Steel

Plastic

	System of Measurement System of Measurement

Inch

Metric

	For ID For ID

	For Maximum Pipe ID For Maximum Pipe ID

	For Shape For Shape


Round	Corner

Rectangle	Square

	Maximum Air Back Pressure Maximum Air Back Pressure

	Material Material

	Plug Type Plug Type


Push In	Expandable

Screw In	Tamper Evident

Snap In	Pull Through

	Profile Profile


Tapered	Straight

	Maximum Temperature Maximum Temperature

	Minimum Temperature Minimum Temperature

	DFARS (Defense Acquisition Regulations Supplement) DFARS (Defense Acquisition Regulations Supplement)

DFARS Specialty Metals
COTS-Exempt

	With Bypass With Bypass

Yes

	Color Color

	Black
	Red
	Clear
	Yellow
	Dark Blue
	Dark Brown
	Dark Green
	Dark Red
	Light Brown
	Light Gray
	Off-White
	Silver
	Tan
	White
	Blue
	Brown
	Semi-Clear
	Orange
	Pink
	Gray
	Green
	Purple

	RoHS (Restriction of Hazardous Substances) RoHS (Restriction of Hazardous Substances)

RoHS Compliant

RoHS Compliant with
Exemptions

	Seal Material Seal Material

Rubber

Plastic

	Maximum Water Back Pressure Maximum Water Back Pressure

	REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) REACH (Registration, Evaluation, Authorization and Restriction of Chemicals)

REACH Compliant

	Overall Height Overall Height

	Pipe Size Pipe Size

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1,133 Products

Pressure and Vacuum Monitoring and Control

Wing Nut Expansion Plugs

Twist the wing nut on these plugs to expand the seal.

Hex-Nut Expansion Plugs

Tighten the nut on these plugs to expand the seal.

T-Handle Expansion Plugs

Twist the easy-grip t-handle on these plugs to expand the seal.

Quick-Snap Expansion Plugs

Turn the cam handle to expand the seal, then snap the handle down to hold it in place.

Square-Head Expansion Plugs

Turn the square head of the plug into the sealing ring to close off pipe openings.

Expansion Plugs with Bypass

Use the bypass tube on these plugs to add air, water, and other fluid to your pipeline or to relieve pressure while testing.

Air-Inflatable Plugs

Also known as pneumatic plugs, these plugs conform to wide and out-of-round pipes.

Air- and Water-Inflatable Plugs

Penetrate tight pipe junctures with the most flexible expansion plugs we offer.

Air- and Water-Inflatable Plugs for Y-Joints

These extra-long plugs allow you to seal off two pipes at the same time. They have two separate inflation chambers to release back pressure gradually and prevent splash back as water clears the drain line.

Air-Inflatable Plugs with Bypass

Use the bypass tube on these plugs to add air, water, and other fluid to your pipeline or to relieve back pressure while testing.

Deep-Reach Hex Nut Expansion Plugs with Bypass

Use the bypass tube to add air, water, and fluid or relieve back pressure.

Deep-Reach Wing Nut Expansion Plugs

Insert these plugs deep within your pipe to seal it off from the inside.

Expansion Plugs for Tubing

These plugs are designed for metal and rigid plastic tubing.

Quick-Install Pressure Test Fittings

Tighten these threaded fittings with your hands for a secure connection in testing, flushing, venting, and plugging applications—no tools, tape, or sealant required.

Pressure Test Fittings

Check pressure without permanently installing a gauge.

Tapered Plugs

Expandable Tapered Plugs

Place a plug into an opening and tighten the wing nut—the sides expand to create a seal in holes of varying diameters.

Tapered Plugs

Often used as laboratory stoppers, these rubber plugs have good impact and abrasion resistance. They’re tapered to fit a range of hole diameters.

Hollow Tapered Plugs

The hollow construction allows these plugs to compress for a snug fit in threaded and unthreaded holes of varying diameters.

Tamper-Evident Tapered Plugs

Often used on gas cylinders, these plugs cinch and lock tightly around valve heads to block the ports—they must be cut off making it clear if the cylinder has been tampered with. The plugs are tapered to fit a range of hole diameters.

Miniature Tapered Plugs

Sized to fit small openings, these tiny plugs fit snugly but can be removed easily using the flange. Their tapered design fits a range of hole diameters.

Corks

Lightweight and moisture resistant, these plugs are laboratory-grade 100% natural cork. They’re tapered to fit a range of hole diameters.

Pull-Ring Tapered Plugs

Pull the two built-in rings to quickly remove these plugs. All are tapered to fit a range of hole diameters.

High-Temperature Tapered Plugs

Good for electroplating, paint baking, and powder-coating applications, these plugs withstand temperatures up to 570° F. All are tapered to fit a range of hole diameters.

Expandable High-Temperature Tapered Plugs

Place a plug into an opening and tighten the wing nut—the sides expand to create a seal in holes of varying diameters. Good for paint baking and powder-coating applications, these plugs withstand temperatures up to 450° F.

Hollow High-Temperature Tapered Plugs

The hollow construction allows these plugs to compress for a snug fit in threaded and unthreaded holes of varying diameters. Good for electroplating, paint baking, and powder-coating applications, they withstand temperatures up to 450° F.

Miniature High-Temperature Tapered Plugs

Sized to fit small openings, these tiny plugs fit snugly but can be removed easily using the flange. They withstand temperatures up to 470° F, which makes them good for electroplating, paint baking, and powder-coating applications. All are tapered to fit a range of hole diameters.

Chemical-Resistant Tapered Plugs

These plugs have excellent chemical resistance for masking parts during chemical finishing applications such as plating and anodizing. Their tapered design fits a range of hole diameters.

Food Industry Tapered Plugs

Made of FDA listed materials, these plugs are suitable for food contact. They're tapered to fit a range of hole diameters.

Round Plugs

Threaded Round Plugs for NPT Pipe

Protect internally threaded NPT connections from contaminants during fabrication and storage.

High-Temperature Round Plugs for NPT Pipe

These plugs withstand temperatures up to 600° F to protect internally threaded NPT connections from contaminants during electropainting, paint baking, and powder coating applications.

Threaded Round Plugs for Straight-Thread Pipe

Seal tube and hose fittings to keep their straight threads protected from contaminants during fabrication and storage.

Threaded Round Plugs for BSPT Pipe

Safeguard internally threaded BSPT connections from contaminants during fabrication and storage.

Threaded Round Plugs for 37° Flared Tube

Designed to fit into 37° flared connections such as those found on JIC and SAE fittings, these plugs protect internally threaded connections from contaminants during fabrication and storage.

Sealing Plugs

With a compressible flanged top, these plugs are designed to seal the ends of copper tubing often used in water supply lines, refrigerant lines, and HVAC compressors. All are sized to fit standard copper tube dimensions.

Conductive Round Plugs

With a surface resistivity of less than 10⁵ ohms, these plugs not only dissipate electrical charges, but can be used as an electrical shield.

Snap-In Round Plugs

Flexible ridges or straps hold these plugs in place and allow them to fit a range of hole diameters.

Miniature Pull-Through Round Plugs

Also known as mouse tails, these tiny plugs fit through-hole IDs as small as 0.022”, 0.025", or 0.03”.

Snap-In Rectangular Plugs

Flexible ridges securely hold these plugs in place and allow them to fit a range of hole sizes.

Square Plugs

Metal Square Plugs

More durable than plastic plugs, these provide the most protection from abrasion and impact. Use them to eliminate sharp edges and create a finished look on metal fence and machine-guard posts. Drive them in place with a hammer for a secure fit.

Snap-In Square Plugs

Flexible ridges or straps hold these plugs in place.

Caps

Round Caps

Slide these flexible vinyl caps on and they conform for a snug fit.

Heavy Duty Round Caps

Made of rigid plastic, these caps are more wear resistant than vinyl caps but not as flexible.

Sure-Grip Round Caps

A long, textured pull tab provides a sure grip for quick removal even when wearing gloves.

Chemical-Resistant Round Caps

These caps have excellent chemical resistance for masking parts during chemical finishing applications such as plating and anodizing.

Tapered Caps

These flexible plastic caps are tapered to fit a variety of unthreaded and threaded objects.

Corner Caps

Guard the corners of fragile materials such as glass and mirrors.

Stretchable Sealing Caps

Tug on the pull tabs to stretch these caps onto the tips of bottles, beakers, flasks, and cylinders, creating an airtight seal.

Hinged Fastener Caps

A one-piece hinged design allows frequent access to screw heads without misplacing the top. To conceal and protect the entire screw head, insert your screw through the hole in the base and flip the hinged top over.

Stretchable Flange Caps

Stretch these caps over flared edges such as flanged tubing and valve handles.

Cleanout and Drain Pipe Plugs

Drain Pipe Plugs

Seal unthreaded pipe ends with these plugs. They come with a band that clamps over the outside wall of your pipe and tightens with a screwdriver.

Cleanout Plugs

Close off your drain cleanout pipe with these plugs.