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    25 Products

    Stainless Steel Button Head Hex-Drive Screws

    Image of Product. Front orientation. Rounded Head Screws. Stainless Steel Button Head Hex-Drive Screws.
    These button head screws won't corrode from moisture and chemicals, but they aren't as strong as alloy steel screws. The button head looks similar to a pan head, but it's lower and more compact, taking up less space. With six contact points, the hex drive withstands more torque than slotted and Phillips to securely grip your driver.
    Length is measured from under the head.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these screws won't rust. However, they don't hold up to the harsh chemicals that 316 stainless steel can.
    Head
    Lg.
    Dia.
    Ht.
    Threading
    Tensile Strength,
    psi
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
     
    12-28
    1/2"0.413"0.114"Fully Threaded70,000100000000000000
    3/4"0.413"0.114"Fully Threaded70,00010000000000000
    1"0.413"0.114"Fully Threaded70,00010000000000000
     

    Steel Cup-Tip Set Screws

    Image of Product. Front orientation. Set Screws. Steel Cup-Tip Set Screws.
    Made of alloy steel, these screws are strong enough to hold components without wearing down. The tip has thin edges that dig into surfaces for a secure hold. They often lock gears, pulleys, and other transmission components onto shafts.
    Black-Oxide Alloy Steel—These screws have a dark matte finish that offers minimal corrosion resistance, so they're best for dry environments.
    Lg.
    Drive
    Size
    Hardness
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Alloy Steel
     
    12-28
    1/4"3/32"Rockwell C45ASME B18.3, ASTM F9121000000000000000
    3/8"3/32"Rockwell C45ASME B18.3, ASTM F912100000000000000
    1/2"3/32"Rockwell C45ASME B18.3, ASTM F912100000000000000
     

    Hex Nuts

    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    The most commonly used hex nuts, these are suitable for fastening most machinery and equipment.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these nuts are about half as strong as medium-strength nuts. They are suitable for light duty fastening applications, such as securing access panels. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Wd.
    Ht.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    12-28
    7/16"5/32"ASME B18.2.210000000000000000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They resist rust in wet and outdoor environments, but won't hold up to the harsh chemicals that 316 stainless steel can.
    Highly Corrosion-Resistant Black-Oxide 316 Stainless Steel—Combines a finished appearance with the rust resistance of 316 stainless steel. Even if the coating wears off, these nuts will hold up in just about any environment, including salt water and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    12-28
    7/16"5/32"100000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    12-28
    7/16"5/32"250000000000000
     
    Highly Corrosion-Resistant Black-Oxide 316 Stainless Steel
    12-28
    7/16"5/32"10000000000000
     
    Brass
    Brass—Conductive and nonmagnetic, brass nuts are commonly used to secure electrical equipment, such as circuit board assemblies and mounting brackets, inside enclosures. They're also softer than most metals, so they won't damage other fastening components.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Brass
    12-28
    7/16"5/32"50000000000000000
     

    Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknuts.
    Versatile yet economical, these are the most commonly used locknuts. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    12-28
    7/16"5/16"22050000000000000000
     

    Cap Nuts

    Image of Product. Front orientation. Cap Nuts. Cap Nuts.
    Conceal and protect protruding screw threads while fastening parts together. These nuts help prevent damage to surrounding materials and reduce injuries. Also known as acorn nuts, they have a smooth, rounded head that creates a finished look.
    Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Pkg.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    18-8 Stainless Steel
    12-28
    7/32"3/8"13/32"1000000000000000000000000
     

    Mil.-Spec. Key-Locking Threaded Inserts For Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Mil.-Spec. Key-Locking Threaded Inserts For Soft Metal.
    These inserts are manufactured and tested to meet or compare to strict standards adopted by the U.S. military. The keys drive into aluminum and other soft metal for a secure hold that won't slip or rotate, even in vibrating vehicle or aerospace parts. These inserts are comparable to Keensert inserts.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limitations.
    High-Strength Cadmium-Plated Alloy Steel—These inserts have the strength to stand up to high-pressure applications and a plating that helps screws thread in smoothly.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Specs. Met
    Each
    Each
    Thin Wall
     
    High-Strength Cadmium-Plated Alloy Steel
    6-32
    12-28
    0.188"3/16"
    0.190"2MS51830A103000000000000000000000000000000
     
    18-8 Stainless Steel
    6-32
    12-28
    0.172"3/16"
    0.190"2MS51830-103000000000000000000000000000
     

    Closed-End Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Closed-End Key-Locking Threaded Inserts for Soft Metal.
    Image of Product. Shown In Cross Section. Side1 orientation. Threaded Inserts. Closed-End Key-Locking Threaded Inserts for Soft Metal.

    Shown

    In

    Cross

    Section

    Keep threads clear and prevent leaks. These inserts have a closed end that blocks debris and fluids from entering parts. Keys drive into soft metal, such as aluminum, so they don’t slip or rotate in the hole. Comparable to Keensert inserts, they’re more secure than thread-locking inserts.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limitations.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Specs. Met
    Each
    Each
    Thin Wall
     
    18-8 Stainless Steel
    6-32
    12-28
    0.375"3/16"
    0.187"2MIL-I-45914000000000000000000000000000000
     

    Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Key-Locking Threaded Inserts for Soft Metal.
    Add strong threads in soft metal, such as aluminum. The keys on these inserts drive into holes to hold more securely than thread-locking or helical inserts. They prevent slipping and rotating, so they’re stable enough for use in vehicle or aerospace parts that experience heavy vibration. These inserts are comparable to Keensert inserts.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limitations.
    High-Strength High-Temperature A286 Stainless Steel—High temperatures won't reduce the load capacity of these inserts. They also resist chemicals such as bleach and chlorine.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Specs. Met
    Each
    Each
    Thin Wall
     
    High-Strength High-Temperature A286 Stainless Steel
    6-32
    12-28
    0.172"3/16"
    0.187"2MS51830CA103000000000000000000000000000000
     

    Seize-Resistant Swage-Locking Threaded Inserts

    Image of Product. Bottom orientation. Threaded Inserts. Seize-Resistant Swage-Locking Threaded Inserts.
    Image of Specification. Front orientation. Contains Annotated. Threaded Inserts. Seize-Resistant Swage-Locking Threaded Inserts.
    Smoothly install these inserts for strong threads near the edges and corners of soft metal surfaces. They’re lubricated to prevent sticking as you thread them in. Since these have thinner walls than our key-locking and thread-locking inserts, they don’t need as much space and won't bulge or crack the material. The knurls press (swage) into the material to keep inserts in place when you tighten or loosen a screw.
    To install these inserts, you need a drill bit, a counterbore, a standard tap, an installation tool, and a hammer. Drill a hole, counterbore the top, and tap it. Place the insert into the installation tool, then hand-tighten it into the tapped hole. Strike the tool to secure the insert and drive the knurls into the surrounding material.
    High-Strength Dry-Film-Lubricated Cadmium-Plated Alloy Steel—Stronger than our 17-4 PH stainless steel inserts, these inserts absorb impact without cracking and stand up to high-pressure applications. The cadmium plating prevents corrosion in wet environments.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Inserts
    Installation
    Tools
    For
    Counterbore
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    For Max.
    Hole Dia.
    Dia.
    Dp.
    Mil. Spec.
    Each
    Each
    High-Strength Dry-Film-Lubricated Cadmium-Plated Alloy Steel
    8-32
    12-28
    0.250"0.191"0.216"0.065"MIL-DTL-45932/100000000000000000000000000000
     

    Swage-Locking Threaded Inserts

    Image of Product. Bottom orientation. Threaded Inserts. Swage-Locking Threaded Inserts.
    Image of Specification. Front orientation. Contains Annotated. Threaded Inserts. Swage-Locking Threaded Inserts.
    Add strong threads to the edges of soft metal without bulging or cracking the material. These inserts have thinner walls than our key-locking and thread-locking inserts, so they don’t need as much space around them. The knurls press (swage) into the material to keep inserts in place when you tighten or loosen a screw.
    To install these inserts, you need a drill bit, a counterbore, a standard tap, an installation tool, and a hammer. Drill a hole, counterbore the top, and tap it. Place the insert into the installation tool, then hand-tighten it into the tapped hole. Strike the tool to secure the insert and drive the knurls into the surrounding material.
    High-Strength 17-4 PH Stainless Steel—The strongest stainless steel inserts we offer. They handle high-stress installations, such as pump and compressor housings, and the heavy vibration of aircraft parts. They won’t rust in wet and outdoor environments but can’t withstand the harsh chemicals and acids that 316 stainless steel can.
    Inserts
    Installation
    Tools
    For
    Counterbore
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    For Max.
    Hole Dia.
    Dia.
    Dp.
    Mil. Spec.
    Each
    Each
    High-Strength 17-4 PH Stainless Steel
    8-32
    12-28
    0.250"0.191"0.216"0.065"MIL-DTL-45932/100000000000000000000000000000
     

    Thread-Locking Threaded Inserts

    Image of Product. Bottom orientation. Threaded Inserts. Thread-Locking Threaded Inserts.
    With Loctite® adhesive already on the threads, these inserts won’t back out or vibrate loose. The adhesive reaches full strength after 72 hours. Unlike helical inserts, you can install them with a standard drill and tap. However, thread-locking inserts are difficult to remove and reuse.
    After drilling and tapping your hole, install inserts with a wrench or an installation bit. To use a wrench, thread an insert and two hex nuts onto a bolt. Then, grip and turn the top nut to drive into the hole. For slotted inserts, you can drive with a slotted screwdriver instead.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limits.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Drive
    Style
    Pkg.
    Qty.
    Pkg.
    Each
    Thin Wall
     
    18-8 Stainless Steel
    6-32
    12-28
    0.280"14 Ga.
    0.182"Slotted
    5000000000000000000000000000000
     

    Screw-Locking Seize-Resistant Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Screw-Locking Seize-Resistant Key-Locking Threaded Inserts for Soft Metal.
    Create the tightest hold in aluminum and other soft metal without screws sticking. The lubricant on these inserts eases installation, and the irregularly shaped threads won’t let screws back out from vibration. Inserts have keys that drive into material to prevent them from slipping or rotating in the hole.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limitations.
    Dry-Film-Lubricated Cadmium-Plated Steel—The plating creates a barrier against rust.
    Dry-Film-Lubricated 18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Specs. Met
    Each
    Each
    Thin Wall
     
    Dry-Film-Lubricated Cadmium-Plated Steel
    6-32
    12-28
    0.172"3/16"
    0.187"2MS51830A103L00000000000000000000000000000
     
    Dry-Film-Lubricated 18-8 Stainless Steel
    6-32
    12-28
    0.172"3/16"
    0.187"2MS51830-103L000000000000000000000000000
     
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