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    12 Products

    Mil. Spec. Distorted-Thread Flange Nuts

    Image of Product. Front orientation. Flange Nuts. Mil. Spec. Distorted-Thread Flange Nuts.
    Not only do these have the strongest hold of all the flange nuts we offer, they are also manufactured and tested to strict U.S. military standards for material and construction. They have irregularly shaped threads that grip the screw to resist loosening in high-vibration applications. The threads prevent the nut from backing out, but they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch, so they are not reusable. Nuts have a flange that distributes pressure evenly across the mounting surface without the need for a separate washer. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. Also known as collar nuts.
    Low-Strength Steel
    About half the strength of medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Cadmium-Plated Steel—The plating reduces friction during installation, so these nuts thread on smoother than others. It also creates a barrier against rust that's comparable to zinc yellow-chromate plating.
    Cadmium Yellow-Chromate-Plated Steel—Better corrosion resistance than plain cadmium. These nuts withstand salt water and are suitable for most wet and outdoor environments.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Mil.
    Spec.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    2-56
    		1/8"3/32"0.167"0.01"MS21042L02500000000000000
     
    Cadmium Yellow-Chromate-Plated Steel
    2-56
    		1/8"3/32"0.167"0.01"MS21042-0250000000000000
     
    Corrosion-Resistant Stainless Steel
    High-Temperature A286 Stainless Steel—Stronger than 316 stainless steel and withstand high temperatures up to 1500° F. These nuts resist corrosion from chemicals, such as bleach and chlorine, but they won't hold up to salt water as well as 316 stainless steel.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    High-Temperature A286 Stainless Steel
    2-56
    		1/8"3/32"0.167"0.01"NAS1291C02M5000000000000000
     

    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.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. 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.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    2-56
    		1/4"9/64"22010000000000000000
     
    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.
    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.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    2-56
    		1/4"9/64"2205000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    2-56
    		1/4"9/64"2205000000000000000
     

    Thin-Profile Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Thin-Profile Nylon-Insert Locknuts.
    About half the height of standard-profile locknuts, these fit in spaces with low clearance. You can also use them as jam nuts by threading them against a hex nut to hold it in place. 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.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. 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.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    2-56
    		1/4"7/64"220100000000000000000
     

    Thread-Forming Locknuts

    Image of Product. Bottom orientation. Locknuts. Thread-Forming Locknuts.
    Form threads into these nuts for a tight fit that won't loosen under vibration. They are partially threaded, so when you fasten them onto metal screws, the tightening action will cut the rest of the threads. Nuts are not reusable.
    Plastic
    Nylon 6/6—Slippery and abrasion resistant, these nuts thread on smoothly and stand up to daily wear and tear. Nylon will swell and weaken when exposed to moisture, so it's best for dry environments.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    White Nylon 6/6
    2-56
    		3/16"1/16"100000000000000000
     

    Mil. Spec. Thin-Profile Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Mil. Spec. Thin-Profile Nylon-Insert Locknuts.
    These locknuts are manufactured and tested to strict U.S. military standards for material and construction. They are about half the height of standard-profile locknuts to fit in spaces with low clearance. You can also use them as jam nuts by threading them against a hex nut to hold it in place. 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.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    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.
    Mil.
    Spec.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    2-56
    		1/4"7/64"MS21083C02250NASM210835000000000000000
     

    Mil. Spec. Nylon-Insert Locknuts

    These locknuts are manufactured and tested to strict U.S. military standards for material and construction. 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
    Image of Product. Front orientation. Locknuts. Mil. Spec. Nylon-Insert Locknuts.
    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.
    Mil. Spec.
    Insert Max.
    Temp., ° F
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    2-56
    		1/4"9/64"MS17830-02C, MS21044C02250NASM17830, NASM21044100000000000000
     

    Flex-Top Locknuts for Heavy Vibration

    Image of Product. Front orientation. Locknuts. Flex-Top Locknuts for Heavy Vibration.
    The top section of these nuts expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. They’re often used in equipment with constant, vigorous vibration, such as engines. 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.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    2-56
    		1/4"5/32"5000000000000000
     

    Press-Fit Locknuts for Sheet Metal

    Image of Product. Bottom orientation. Press-Fit Nuts. Press-Fit Locknuts for Sheet Metal.
    Image of Product. Bottom orientation. Press-Fit Nuts. Press-Fit Locknuts for Sheet Metal.
    The nylon insert inside these nuts grips screws so they won't back out or loosen. Use them to keep thin parts fastened on engines and other vibrating machinery.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust and mild chemicals.
    Thread
    Size
    Drill Bit
    Size
    For Min.
    Panel Thk.
    For Maximum Panel
    Hardness
    Head
    Ht.
    Flange
    Dia.
    Pkg.
    Qty.
    Pkg.
    Nylon-Insert Locking
     
    18-8 Stainless Steel
    2-56
    		1/8"
    		0.05"Brinell 240, Rockwell B1000.08"0.17"10000000000000000
     
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