Square Heads | McMaster-Carr

	System of Measurement System of Measurement

Inch

Metric

	Thread Size Thread Size

	Pipe Size Pipe Size

	Thread Type Thread Type

	Length Length

	Material Material

	Head Type Head Type


Square	T-Slot

	Head Width Head Width

	Head Height Head Height

	Threading Threading

	Fully Threaded
	Partially Threaded

	Tip Type Tip Type


Cup	Extended

	For Pipe Material For Pipe Material

	For Shape For Shape


Square	Rectangle

Round

	Specifications Met Specifications Met

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

DFARS Specialty Metals
COTS-Exempt

DFARS Specialty Metals
Compliant

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

RoHS Compliant

RoHS Compliant with
Exemptions

	Thread Fit Thread Fit

	For Use With For Use With

	Finish Finish

Zinc Yellow-Chromate Plated

Zinc-Phosphate Coated

	Hardness Hardness

	Fastener Strength Grade/Class Fastener Strength Grade/Class

	For Inside Width For Inside Width

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

REACH Compliant

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992 Products

Screws and Bolts

Steel Square-Head Cup-Point Set Screws

Use these steel set screws for light duty holding.

18-8 Stainless Steel Square-Head
Cup-Point Set Screws

These set screws have good chemical resistance.

Super-Corrosion-Resistant 316 Stainless
Steel Square-Head Cup-Point Set Screws

More corrosion resistant than 18-8 stainless steel set screws, these have excellent resistance to chemicals and salt water.

Alloy Steel Square-Head Cup-Point Set Screws

Alloy steel set screws dig into hard surfaces for a secure hold.

Metric Square-Head Extended-Tip Set Screws

These metric screws have a square head, so you can turn them by hand or use a wrench for more torque. Also known as half dog-point set screws, they have a protruding tip that locks within a mating hole or slot to keep parts aligned.

Square-Head Extended-Tip Set Screws

Use the square head to turn these screws by hand, or use a wrench when you need more torque. Also known as half dog-point set screws, they have a protruding tip that locks within a mating hole or slot to keep parts aligned.

Medium-Strength Grade 5 Steel Square Head Screws

Made from Grade 5 steel, these screws are suitable for fastening most machinery and equipment. Large flat sides make these screws easy to grip with a wrench and keep them from rotating in square holes.

Low-Strength Grade A Steel Square Head Screws

About half the strength of medium-strength screws, these screws are for light duty fastening applications, such as securing access panels. Large flat sides make these screws easy to grip with a wrench and keep them from rotating in square holes.

High-Strength Grade 8 Steel Square Head Screws

Made from Grade 8 steel, these screws can be used in high-stress applications, such as valves, pumps, motors, and automotive suspension systems. Large flat sides make these screws easy to grip with a wrench and keep them from rotating in square holes.

Metal Pipe and Pipe Fittings

Low-Pressure Galvanized Iron
and Steel Threaded Pipe Fittings

The galvanized finish on these fittings provides fair corrosion resistance. Fittings are for use in low-pressure applications.

Low-Pressure Galvanized Steel
Threaded Pipe Fittings with Sealant

The male threads on these fittings have a sealant applied for extra leak protection.

Low-Pressure Iron and Steel Threaded Pipe Fittings

Use these fittings for low-pressure applications in noncorrosive environments.

Low-Pressure Cast Iron Threaded Pipe Fittings

Compact Extreme-Pressure
Steel Threaded Pipe Fittings

These fittings are strong enough to handle extreme pressures, yet small enough to fit into cramped spaces.

High-Pressure Iron and Steel Threaded Pipe Fittings

These fittings can stand up to high-pressure applications. Use them in noncorrosive environments.

Medium-Pressure Iron and Steel Threaded Pipe Fittings

For use in noncorrosive environments, these fittings have better strength than our low-pressure iron and steel pipe fittings.

High-Pressure Stainless Steel Threaded Pipe Fittings

Use these heavy duty, corrosion-resistant fittings in high-pressure flow applications.

Low-Pressure Stainless Steel Threaded Pipe Fittings

Use these corrosion-resistant fittings in a low-pressure pipe line.

Low-Pressure Stainless Steel
Threaded Pipe Fittings with Sealant

The male threads on these fittings have a sealant applied for extra leak protection.

Low-Pressure Plated Brass Threaded Pipe Fittings

Used in low-pressure pipe lines, these brass fittings have a plating that makes them shiny and improves corrosion resistance.

Low-Pressure Brass and Bronze Threaded Pipe Fittings

Use these fittings in low-pressure flow applications. They have good corrosion resistance.

Low-Pressure Brass Threaded
Pipe Fittings with Sealant

The male threads on these brass fittings have a sealant applied for extra protection against leaks. Also known as Pressure Class 125 fittings, they are built for use in low-pressure applications.

High-Pressure Brass Threaded Pipe Fittings

These brass fittings have the strength to handle high-pressure applications.

High-Pressure Brass Threaded
Pipe Fittings with Sealant

Not only do these brass fittings have the strength to handle high-pressure applications, the male threads have a sealant applied for extra protection against leaks.

Extreme-Pressure Brass Threaded Pipe Fittings

Extreme pressures are no problem for these heavy-duty brass fittings.

Titanium Threaded Pipe Fittings

Titanium has similar strength to steel, but is approximately 40% lighter. It has better corrosion resistance than most stainless steel alloys and can handle corrosive substances, such as salt water and acids.

High-Pressure Aluminum Threaded Pipe Fittings

Also known as Pressure Class 3000 fittings, these have the highest pressure rating of all the aluminum pipe fittings we offer.

Low-Pressure Aluminum Threaded Pipe Fittings

In addition to being lightweight, these aluminum fittings offer good corrosion resistance. Use them in low-pressure flow applications.

Medium-Pressure Aluminum Threaded Pipe Fittings

Designed for medium-pressure applications, these fittings have better strength than our low-pressure aluminum pipe fittings.

Measuring and Inspecting

Starrett High-Accuracy Combination Square Heads

Attach to Starrett High-Accuracy Combination Square Blades with the included lockbolts.

High-Accuracy Combination Square Heads

Attach to High-Accuracy Combination Square Blades with the included lockbolts.

Center Finders for Curved Surfaces

Center your work by mounting these into your drill chuck or collet and lining up the pointer with the mark on the shaft.

T-Slot Fasteners and Setup Studs

T-Slot Bolts

For quicker setups than a separate T-slot nut and stud, slide these bolts into T-slot tracks on machine tool tables.

T-Slot Cleaners

Scrape debris out of machine table T-slots.

T-Slot Nut and Setup Stud Kits

For mounting items to your machine table, these kits contain the full system of necessary components.

Caps and Plugs

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.

Snap-In Square Plugs

Flexible ridges or straps hold these plugs in place.

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.

Heavy Duty Square Caps

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

Square Caps

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

Heat-Shrink Round Caps

Permanently seal pipe, tubing, conduit, and even crimped electrical connections. Slide these flexible caps on and use a heat gun to tightly shrink them to the shape of whatever they are covering. Their outer surface shrinks while the inner wall flows into voids to create a sealed connection.