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.

Bolt down equipment in food processing or sanitary areas while sealing out contaminants.

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.

Seal out contaminants and prevent leaks—a rubber O-ring under the head prevents leaks and seals out contaminants.

To prevent unwanted removal, these metric screws have a tamper-resistant Torx drive—also known as a pin-in Torx drive—that makes them difficult to unscrew without special tools. An O-ring under the head blocks leaks and seals out dust and dirt.

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.

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.

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.

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.

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.

A zinc plating provides mild corrosion resistance.

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.

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.

These metric screws have a silicone O-ring that prevents leaks and seals out contaminants. Made from 18-8 stainless steel, they have good chemical resistance and may be mildly magnetic.

Prevent unwanted removal, leaks, and contamination with these sealing Torx screws.

With an O-ring under the head, these screws prevent leaks and seal out contaminants.

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

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

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.

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

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