Insert Plugs | McMaster-Carr

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

REACH Compliant

	For Use Outdoors For Use Outdoors

Yes

	Head Diameter Head Diameter

	For Surface Type For Surface Type

Unthreaded

Threaded

	For Inside Width For Inside Width

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2,069 Products

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.

Corks

Lightweight and moisture resistant, these plugs are laboratory-grade 100% natural cork. 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.

Hollow Tapered Plug Assortments

Keep hollow tapered plugs of various sizes on hand to solve whatever problems arise. The hollow construction allows these plugs to compress for a snug fit in threaded and unthreaded holes of varying diameters.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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

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.

Chemical-Resistant Pull-Through Round Plugs

These plugs have excellent chemical resistance for masking parts during chemical finishing applications such as plating and anodizing. Use the smaller end of the plug to pull the larger end into a through hole to form a tight seal.

High-Temperature Pull-Through Round Plugs

Good for electroplating, paint baking, and powder-coating applications, these plugs withstand temperatures up to 600° F. To form a tight seal, use the smaller end of the plug to pull the larger end into a through hole.

Antistatic Round Plugs

Keep equipment safe from electrical currents with these plugs that have a surface resistivity of less than 10¹² ohms.

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”.

Round Plugs

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

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.

Flanged Pull-Through Round Plugs

Designed with a flange, these plugs protect countersunk holes during anodizing, electroplating, paint baking, and powder-coating applications. All withstand temperatures up to 600° F. Use the smaller end of the plug to pull the larger end into a through hole to form a tight seal.

Snap-In Round Plugs

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

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.

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 NPT Pipe

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

Threaded Round Plugs for BSPT Pipe

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

Pull-Tab Round Plugs

A time-saving alternative to threaded plugs, these plugs press in place and have an ergonomic pull tab for quick and easy removal. Use them to temporarily protect holes in objects from contaminants during storage, painting, and light fabrication.

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.

Square Plugs

Snap-In Square Plugs

Flexible ridges or straps hold these plugs in place.

Push-In Square Plugs

Push these plugs into an opening and friction holds them in place.

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.

Domed Square Plugs

Often used on metal furniture, these plugs provide a finished look on posts and tubes. Snap them into place and their flexible ridges will provide a secure grip.

Rectangular Plugs

Snap-In Rectangular Plugs

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

Push-In Rectangular Plugs

Push these plugs into an opening and friction holds them in place.

Panel Plugs

Metal Snap-In Panel Plugs

Made of steel, these are our most durable plugs for panels. Tapered prongs snap into the hole to securely hold them in place.

Metal Snap-In Panel Plug Assortments

Keep metal snap-in plugs of various sizes on hand to solve whatever problems arise. Made of steel, these plugs are our most durable plugs for panels. Their tapered prongs snap into holes to securely hold them in place.

Plastic Snap-In Panel Plugs

Tapered prongs or a snap-in ring securely hold these plugs in place.

Vented Snap-In Panel Plugs

Vents in the top allow air circulation and permit heat and fumes to escape. These plugs have tapered prongs that snap into the hole to securely hold them in place.

Push-In Panel Plugs

Push these plugs into place for a finished appearance on both sides of a panel.

Sealing Panel Plugs

The wings on these plugs expand against the sides of a hole to form a liquid-tight seal. Pierce the plugs with round wire, cable, or tubing and they function as a grommet to create insulated holes.

Locking Panel Plugs

The wings on these plugs expand against the sides of a hole to lock them in place.

Vented Locking Panel Plugs

Vents in the top allow air circulation and permit heat and fumes to escape. All of these plugs have wings that expand against the sides of the hole to lock them in place.

Clear Locking Panel Plugs

These plugs are see-through to provide visibility and light transmission. They have wings that expand against the sides of the hole to lock them in place.

Expansion Plugs for Castings

Also known as freeze plugs, these are commonly used to permanently seal the shallow holes left in a component during the casting process.

Fixture Plate Chip Plugs

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

Ethernet Port Plugs

Shield unused RJ45 type ports on computers and other electronic equipment from debris and moisture.

Hydraulic Sealing Plugs

Permanently seal unthreaded holes in pneumatic and hydraulic components.

Tapered Caps

Tapered Cap Assortments

Keep tapered caps of various sizes on hand to solve whatever problems arise. These flexible plastic caps are tapered to fit a variety of unthreaded and threaded objects.

Tapered Caps

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

Push-In Bumpers

Tight-Grip Push-In Bumpers

A ridge on the stem provides a tighter grip than other push-in bumpers. Push the stem into a hole for quick installation. These bumpers are commonly used as feet on instruments and bench-top equipment to keep them from sliding. They're also good as spacers between sheets of material. Also known as stem and grommet bumpers.

Compressible-Stem Push-In Bumpers

The stem on these bumpers compresses to fit into tight holes. Push the stem into a hole for quick installation. These bumpers are commonly used as feet on instruments and bench-top equipment to keep them from sliding. They're also good as spacers between sheets of material. Also known as stem and grommet bumpers.

Push-In Bumpers

Push the stem into a hole for quick installation. These bumpers are commonly used as feet on instruments and bench-top equipment to keep them from sliding. They're also good as spacers between sheets of material. Also known as stem and grommet bumpers.

Grommets

Cut-to-Size Grommets

Cut the thin layer of rubber in the center of these grommets to create custom IDs to securely hold and protect wire, cable, and cords. Push these grommets into place. They turn rough-edged and uneven holes into smooth, insulated holes. Commonly used in metal panels, they also damp vibration. Also known as webbed grommets.

High-Temperature Grommets

These flexible grommets withstand temperatures of 450° F or greater, which is approximately twice as high as our standard grommets. Push them into place to protect wire, cable, and cords by turning rough-edged and uneven holes into smooth, insulated holes. Commonly used in metal panels, they also damp vibration.

Expandable Grommets

The center hole has flaps that flex to hold and protect various sizes of wire, cable, and cords while keeping out dust and debris. Push these grommets into place. They turn rough-edged and uneven holes into smooth, insulated holes.

Grommet Assortments

Keep grommets of various sizes on hand to solve whatever problems arise.

Grommets

Push these flexible grommets into place to protect wire, cable, and cords by turning rough-edged and uneven holes into smooth, insulated holes. Commonly used in metal panels, they also damp vibration.

Locking Grommets

These grommets snap into place and have wings that expand against the sides of the hole to lock them in position. Use them to protect wire, cable, and cords by turning rough-edged and uneven holes into smooth holes.

Expandable Locking Grommets

The center hole has flaps that flex to hold and protect various sizes of wire, cable, and cords while keeping out dust and debris. Snap these grommets into place and their wings expand against the sides of the hole to lock them in position. Use them to turn rough-edged and uneven holes into smooth holes.

Split Grommets

A slit in the side of these grommets allows you to install them around wire, cable, and cords that are already in place. They snap into the hole and their wings hold them tight. Use them to turn rough-edged and uneven holes into smooth, insulated holes.

Furniture Grommets

Flexible Furniture Grommets

Squeeze these flexible grommets to open the center flap—once wire, cable, and cords pass through, the flap closes tightly for dust and debris protection as well as a finished look. Use them to eliminate cord clutter on desktops, countertops, benchtops, and other work surfaces.

Furniture Grommets

Eliminate clutter on desktops, countertops, benchtops, and other work surfaces by organizing wire, cable, and cords.

Expandable Furniture Grommets

The center hole has flaps that flex to accommodate various sizes of wire, cable, and cords while still providing dust and debris protection. Use these grommets to eliminate cord clutter on desktops, countertops, benchtops, and other work surfaces.

Brush-Style Furniture Grommets

Wire, cable, and cords pass through the grommet opening while the bristles fill in the gaps to control dust and debris. Use these grommets to eliminate cord clutter on desktops, countertops, benchtops, and other work surfaces.

Shaft Grommets

Support shafts, bearings, and other moving parts that are routed through a hole. These grommets are slippery to allow parts to move freely in the hole. Install them on thin sheet-metal panels.

Sealing Grommets

Liquid-Tight Sealing Grommets

Rated IP68, these grommets form liquid-tight seals around wire, cable, and cords to protect them against dust as well as submersion in a maximum of one meter of water.

Split Sealing Grommets

The two‐piece design makes it easy to install and seal these grommets around wire, cable, and cords that are already in place. Use them to keep out dust, debris, and moisture.

Shrink-to-Fit Sealing Grommets

Apply heat and these grommets shrink around wire, cable, and cords to keep out dust, debris, and moisture.

Create-Your-Own Split Sealing Grommets

Cut the center of these grommets with a utility knife to create custom IDs. The two‐piece design makes it easy to install and seal these grommets around wire, cable, and cords that are already in place. Use them to keep out dust, debris, and moisture.

Pipe and Tubing Grommets

Snap-In Pipe and Tubing Grommets

These grommets have two flanges that snap around holes and flex to compensate for misalignment and movement of pipe and tubing. They're often used for routing applications in panel walls.

Push-In Pipe and Tubing Grommets

Press these flexible grommets into holes and their tapered inner wall will expand when pipe or tubing is inserted to hold them snugly in place. They're often used for routing applications on metal, plastic, and fiberglass tanks.

Fabric Grommets

Reinforcing Fabric Grommets

The extended neck on the washer of these grommets adds reinforcement so you can use them in thicker material such as woven fabrics. Press them into a hole you've already cut. They strengthen and prevent holes from fraying in tarps, covers, and curtains. They also provide a way to run rope and cable through your material.

Rolled-Rim Reinforcing Fabric Grommets

A rolled rim provides added grip while the elongated neck and teeth on the washer, also known as a spur washer, add reinforcement and reduce rotation so you can use these grommets in thick materials such as canvas. Press the grommets into a hole you've already cut. They strengthen and prevent holes from fraying in tarps, covers, and curtains. They also provide a way to run rope and cable through your material.

Fabric Grommet Kits

Kits include grommets, a cutting punch, a cutting block, an installation punch, and a die set. Use them to create a way to run rope and cable through tarps, covers, and curtains.

Snap-In Fabric Grommets

No setting tools needed—snap the two parts together in a hole you've already cut to strengthen the hole and eliminate fraying. Use these grommets in tarps, covers, curtains, and other material.

Self-Piercing Fabric Grommets

The sharp neck on these grommets cuts the material as you press them into place, eliminating the need for a cutting punch. They strengthen and prevent holes from fraying in tarps, covers, and curtains. They also provide a way to run rope and cable through your material.

Fabric Grommets

Press these grommets into a hole you've already cut. They strengthen and prevent holes from fraying in tarps, covers, and curtains. They also provide a way to run rope and cable through your material.

Snap-In Hole Plugs

Seal unused holes and knockouts in enclosures and outlet boxes.