Hole Plugs | McMaster-Carr

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9,629 Products

Building and Machinery Hardware

Protective Plugs

Protective Plugs

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

Protective Caps

Protective Caps

Cover holes at the end of pipe, conduit, and fittings to keep out debris

Grommets

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

Bumpers

Absorb impact to protect equipment and surfaces from dents and scuffs

Slip-On Framing and Fittings

Slip-On Framing and Fittings

Insert rails into fittings and tighten screws to make guards, railings, and racks

Strut Channel Framing and Fittings

Strut Channel Framing and Fittings

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

Vibration-Damping Mounts

Vibration-Damping Mounts

Attach to machinery to reduce vibration and noise and extend service life

Electrical

Electrical Enclosure Plugs

Electrical Enclosure Plugs

Cover unused holes in enclosures to keep out dust, dirt, and moisture

Electrical Enclosure Vents

Electrical Enclosure Vents

Attach to sealed enclosures so air can flow to equalize temperature and pressure

Electrical Enclosure Drains

Electrical Enclosure Drains

Release moisture to keep components dry

Electrical Enclosure Drain Vents

Electrical Enclosure Drain Vents

Prevent moisture from getting trapped inside enclosures while letting air flow through

Cord Grips

Securely connect cords to enclosures while sealing out dirt and moisture

Cable Entry Panels

Cable Entry Panels

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

DIN Rail Caps

Guard the edges of DIN rail from damage and create a finished look

Heat-Shrink Tubing

Heat-Shrink Tubing

Apply heat to seal and insulate electrical wiring and connections

Electrical Connectors and Cords

Electrical Connectors and Cords

Supply power to equipment by combining plugs, sockets, receptacles, and cords

Electrical Connector Caps

Electrical Connector Caps

Protect data connectors when not in use

Data Port Locks

Data Port Locks

Block USB or Ethernet ports from unauthorized use

Electrical Connector Clips

Electrical Connector Clips

Attach to data connectors to lock them in place, repair them, or color code them

Circuit Breaker Box Filler Plates

Circuit Breaker Box Filler Plates

Conceal live electrical components in circuit breaker boxes to prevent injury and damage

Capacitor Boots

Capacitor Boots

Shield capacitors and wire connections to extend their service life and reduce accidental shocks

Fluid Handling

Expansion Plugs

Expansion Plugs

Seal pipe and tubing lines when checking for leaks

Bore Sealing Plugs

Bore Sealing Plugs

Permanently seal unthreaded holes in pneumatic and hydraulic components

Drain Valves

Vent air or discharge liquids to remove excess fluid from your system

Pipe and Pipe Fittings

Pipe and Pipe Fittings

Generally thicker and more rigid than tubing for distributing liquids and gases through your facility

Tube and Tube Fittings

Tube and Tube Fittings

Typically more flexible than pipe for carrying liquids and gases in short runs around equipment

Hose and Hose Fittings

Hose and Hose Fittings

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

Breather Vents

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

Pressure Test Fittings

Pressure Test Fittings

Create a temporary connection point for gauges and other testing equipment

Heat Exchanger Plugs

Heat Exchanger Plugs

Plug leaky internal tubes in heat exchangers

Fabricating and Machining

Fixture Plate Plugs

Fixture Plate Plugs

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

Fastening and Joining

Standoff Caps

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

Quick-Release Pin Receptacles

Quick-Release Pin Receptacles

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

Quick-Release Pin Retaining Caps

Quick-Release Pin Retaining Caps

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

Rivets

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

Press-Fit Nuts

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

Retaining Rings

Retaining Rings

Hold components on a shaft

Safety Equipment

Earplugs

Protect your hearing in loud environments without the bulk of earmuffs

Fire Hydrant Caps

Fire Hydrant Caps

Pair with a hook-style spanner wrench to quickly cover and uncover fire hydrants

Fire Stops

Prevent fire and smoke from passing through holes in fire-resistant walls and floors

Fire Hydrant Plugs

Fire Hydrant Plugs

Pair with a hook-style spanner wrench to quickly seal fire hydrants and washdown equipment

Spill-Control Drain Covers

Spill-Control Drain Covers

Block grates and manholes so liquid can't get in and odors can't get out

Floor Drain Plugs

Floor Drain Plugs

Prevent oil and other spills from going down your floor drain

Facility and Grounds Maintenance

Faucet Hole Covers

Faucet Hole Covers

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

Shower Stoppers

Shower Stoppers

Push down to plunge and cut trapped material to prevent clogs

Sink Drains

Empty liquids from sinks into sewer lines

Sink Drain Stoppers

Sink Drain Stoppers

Plug drains to fill up sinks and tubs

Floor Drain Trap Seals

Floor Drain Trap Seals

Stop sewer gases from escaping through rarely used floor drains if the P-trap dries out

Drain Check Valves

Drain Check Valves

Prevent water damage by placing into floor drains to stop sewer back-ups

Drain Cleanouts

Drain Cleanouts

Create an access point to inspect and clean floor drain pipelines

Rebar Caps

Brightly colored to alert workers to exposed rebar and pipe

Containers, Storage, and Furniture

Drum Plugs

Seal drum lid openings

Drum-Plug Caps

Access inside drums to fill them

Drum Locks

Secure drum lids and openings to prevent tampering

Dust Covers

Stretch over drums, pails, and other objects to keep out dust and debris

Stacking Caps and Targets

Stacking Caps and Targets

Turn the ends of posts into stackable shelving and rack systems

Lubricating

Oil Fittings

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

Oil Cups

Instead of manually lubricating equipment, a built-in reservoir gradually delivers oil

Grease Fitting Caps

Grease Fitting Caps

Protect grease fittings from dirt, debris, and moisture

Communication

Tamper-Evident Seals

Tamper-Evident Seals

Secure hasps, latches, and other connections to visibly indicate tampering

Material Handling

Conveyor Guide Mounting Rod Caps

Conveyor Guide Mounting Rod Caps

Cover the ends of conveyor guide mounting rods for a finished look

Heating, Ventilation, and Air Conditioning

Air Conditioner Service Valve Caps

Air Conditioner Service Valve Caps

Seal off AC service valves to prevent refrigerant from leaking out

The quick brown fox jumped over the lazy dog. Pedestal (35" Ht. x 4" Wd. x 4" Dp.)