Sems Bolts | McMaster-Carr

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	Screw Features Screw Features


Sealing	With Washer

Cutting Wings

	Locking Type Locking Type

	Lock Washer

	System of Measurement System of Measurement

Inch

Metric

	Thread Size Thread Size

	Length Length

	Head Type Head Type


Hex	Socket

Rounded	Flat

	Material Material

Stainless Steel

Steel

Zinc

	Finish Finish

Corrosion-Resistant-Coated

Passivated

Zinc Plated

	Washer Type Washer Type


Flat	Split Lock

External-Tooth Lock	Spring Lock

Internal-Tooth Lock	Sealing

Conical

	Drive Style Drive Style


External Hex	Hex

Phillips	Square

	Threading Threading

	Fully Threaded
	Partially Threaded

	Washer Material Washer Material

Stainless Steel/Rubber

Aluminum/Rubber/Steel

	Thread Direction Thread Direction

	Right Hand

	Head Height Head Height

	Head Width Head Width

	Washer OD Washer OD

	Head Diameter Head Diameter

	Rounded Head Style Rounded Head Style


Pan	Truss

	Tensile Strength Tensile Strength

	Washer Thickness Washer Thickness

	Socket Head Profile Socket Head Profile

	Standard

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

RoHS Compliant

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

REACH Compliant

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759 Products

About Rounded Head Screws

Hex Head Screws with Lock Washer

Also known as Sems screws, these screws have a permanently attached but freely rotating tooth lock washer that bites into the mating surface for vibration resistance.

Hex Head Screws with Flat Washer

A freely rotating but permanently attached washer distributes pressure over a wider area than a flange, preventing damage to your material's surface.

Socket Head Screws

Stainless Steel Socket Head
Screws with Split Lock Washer

Stainless steel screws have excellent corrosion resistance in most environments. They have a split lock washer to create tension and resist loosening from vibration.

Alloy Steel Socket Head Screws with Split Lock Washer

With a tensile strength of 180,000 psi, these alloy steel screws are among the strongest we carry. They are stronger than Grade 8 steel screws and more than two and a half times stronger than stainless steel screws with split lock washer. The split lock washer helps to resist vibration.

Socket Head Screws with Flat Washer

A freely rotating washer distributes pressure over a wider area than a flange, preventing damage to your material's surface.

Rounded Head Screws with Lock Washer

Metric Steel Pan Head Screws
with Internal-Tooth Lock Washer

These metric screws have a washer with sharp internal teeth that dig into surfaces to resist large amounts of vibration. The smooth outside edge of the washer provides a finished look. Also known as Sems screws, the washer rotates freely but is permanently attached.

Steel Pan Head Screws with
Internal-Tooth Lock Washer

Sharp internal teeth dig into surfaces to resist large amounts of vibration, while the smooth outside edge provides a finished look. Also known as Sems screws, the washer rotates freely but is permanently attached.

Stainless Steel Pan Head Screws
with Internal-Tooth Lock Washer

These stainless steel screws have good chemical resistance and may be mildly magnetic. The washer has sharp internal teeth that dig into surfaces to resist large amounts of vibration while the smooth outside edge provides a finished look. Also known as Sems screws, the washer rotates freely but is permanently attached.

Metric Stainless Steel Pan Head Screws
with Internal-Tooth Lock Washer

Made from stainless steel, these metric screws have good chemical resistance and may be mildly magnetic. The washer has sharp internal teeth that dig into surfaces to resist large amounts of vibration while the smooth outside edge provides a finished look. Also known as Sems screws, the washer rotates freely but is permanently attached.

Steel Pan Head Screws with
External-Tooth Lock Washer

The washer on these screws has sharp external teeth that dig into surfaces for maximum holding power and vibration resistance. Also known as Sems screws, the washer rotates freely but is permanently attached.

Metric Steel Pan Head Screws
with External-Tooth Lock Washer

These metric screws have a washer with sharp external teeth that dig into surfaces for maximum holding power and vibration resistance. Also known as Sems screws, the washer rotates freely but is permanently attached.

Metric Stainless Steel Pan Head Screws
with External-Tooth Lock Washer

These metric stainless steel screws have good chemical resistance and may be mildly magnetic. All have a washer with sharp external teeth that dig into surfaces for maximum holding power and vibration resistance. Also known as Sems screws, the washer rotates freely but is permanently attached.

Stainless Steel Pan Head Screws
with External-Tooth Lock Washer

Made from stainless steel, these screws have good chemical resistance and may be mildly magnetic. All have a washer with sharp external teeth that dig into surfaces for maximum holding power and vibration resistance. Also known as Sems screws, the washer rotates freely but is permanently attached.

Metric Stainless Steel Pan Head
Screws with Spring Lock Washer

These metric stainless steel screws have good chemical resistance and may be mildly magnetic. A curved washer protects delicate surfaces while providing constant tension. Also known as Square Cone Sems screws, the washer rotates freely but is permanently attached.

Stainless Steel Pan Head
Screws with Spring Lock Washer

Made from stainless steel, these screws have good chemical resistance and may be mildly magnetic. A curved washer protects delicate surfaces while providing constant tension. Also known as Square Cone Sems screws, the washer rotates freely but is permanently attached.

Steel Pan Head Screws with Spring Lock Washer

A zinc plating provides mild corrosion resistance.

Pan Head Screws with Flat and Split Lock Washer

The flat washer distributes holding pressure and protects delicate surfaces from damage while the split lock washer adds tension to prevent loosening from small amounts of vibration.

Metric Steel Pan Head Screws with Split Lock Washer

As you tighten these metric screws, the split lock washer flattens to add tension and prevent loosening from small amounts of vibration. Also known as Sems screws, the washer rotates freely but is permanently attached.

Steel Pan Head Screws with Split Lock Washer

When compressed, the split lock washer flattens to add tension and prevent loosening from small amounts of vibration. Also known as Sems screws, the washer rotates freely but is permanently attached.

Stainless Steel Pan Head Screws with Split Lock Washer

Stainless steel screws have excellent corrosion resistance in most environments.

Tapping, Wood, and Drywall Screws

Steel Drilling Screws with Washer for Metal

These steel screws are available with corrosion resistant finishes. A rubber-bonded washer compresses to form a watertight seal. They save you time and effort by drilling their own holes and fastening in a single operation.

Steel Drilling Screws with Corrosion-Resistant
Head and Washer for Metal

These steel screws have a head encapsulated by 18-8 stainless steel.

Stainless Steel Drilling Screws with Washer for Metal

Made from 410 stainless steel, these screws are strong, wear resistant, and mildly chemical resistant.

Drilling Screws for Joining Fabric to Metal

These screws have a free-rotating, permanently attached washer that remains stationary while tightening to prevent bunching while attaching tarps and other fabric to metal.

Rounded Head Screws with Washer for Sheet Metal

A free-rotating, permanently attached washer distributes holding pressure over a wider area than a flange and remains stationary to prevent scratching the material surface as you tighten the screw.

Stainless Steel Vibration-Damping
Hex Head Screws for Sheet Metal

Made from 18-8 stainless steel, these screws are chemical resistant.

Steel Vibration-Damping Hex
Head Screws for Sheet Metal

These steel screws are zinc plated to resist corrosion in wet environments.

Screws for Joining Sheet Metal to Wood

Able to penetrate overlapping sheets, these screws have a secure hold in wood.

Sealing Screws for Softwood
and Plastic-Wood Composites

The neoprene-backed washer seals out contaminants.

Rounded Head Screws for Joining Plastic to Wood

Cutting wings under the head allow plastic to expand and contract without cracking. A washer made from aluminum and rubber bonded to steel adds a watertight seal.

Stainless Steel Hex Head Screws
for Joining Plastic to Wood

18-8 stainless steel screws have good chemical resistance.

Steel Hex Head Screws for Joining Plastic to Wood

These steel screws are zinc plated to resist corrosion in wet environments.