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    9 Products
    About Hex Nuts
    industrial info icon

    Choose a hex nut with the right profile, material, and strength for your application.

    Thin-Profile Hex Nuts

    Image of Product. Front orientation. Hex Nuts. Thin-Profile Hex Nuts.
    About half the height of standard-profile nuts, these fit in spaces with low clearance. You can also use them as jam nuts by threading them against another hex nut to hold it in place.
    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.
    Thread
    Size
    Wd.
    Ht.
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/2"-20
    		3/4"5/16"Material Certificate
    		2591847A52500000
     
    Black-Oxide 18-8 Stainless Steel
    1/2"-20
    		3/4"5/16"—1098514A1400000
     

    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.
    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
    1/2"-20
    		3/4"5/16"220590101A25500000
     
    Black-Oxide 18-8 Stainless Steel
    1/2"-20
    		3/4"5/16"220590101A1260000
     

    Mil. Spec. Thin-Profile Hex Nuts

    These nuts are manufactured and tested to strict U.S. military standards for material and construction. About half the height of standard-profile nuts, they fit in spaces with low clearance. You can also use them as jam nuts by threading them against another hex nut to hold it in place.
    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
    Image of Product. Front orientation. Hex Nuts. Mil. Spec. Thin-Profile Hex Nuts.
    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.
    Thread
    Size
    Wd.
    Ht.
    Mil. Spec.
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/2"-20
    		3/4"5/16"Fed. Spec. FF-N-836, MS35691-39Material Certificate
    		192101A98000000
     

    Left-Hand-Thread Thin-Profile Hex Nuts

    Image of Product. Front orientation. Contains Annotated, MultipleImages. Hex Nuts. Left-Hand-Thread Thin-Profile Hex Nuts.
    These nuts tighten when turned to the left. Use them with left-hand rods and screws to prevent counterclockwise-moving parts from loosening. About half the height of standard-profile nuts, these fit in spaces with low clearance. You can also use them as jam nuts by threading them against another hex nut to hold it in place.
    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.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/2"-20
    		3/4"5/16"594450A280000000
     

    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
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/2"-20
    		3/4"5/16"MS21083C8, NASM21083250197231A490000000
     

    Key-Locking Threaded Insert Assortments with Installation Tools

    Image of Product. Front orientation. Threaded Inserts. Key-Locking Threaded Insert Assortments with Installation Tools.
    What you need to add or repair a range of thread sizes in soft metal, such as aluminum. These assortments include multiple key-locking inserts of each size and an installation tool. They're comparable to Keensert inserts.
    Standard Wall—Stronger than thin-wall inserts, these are your go-to choice for threading most holes.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    No. of Inserts
    Included
    Includes
    Thread
    Spacing
    For Tap Thread Size
    Drill Bit Size
    For Max. Hole Dia.
    Each
    Standard Wall
     
    18-8 Stainless Steel
    771/4"-28 Thread × 3/8" Installed Lg. (20 Each)
    5/16"-24 Thread × 0.438" Installed Lg. (15 Each)
    3/8"-24 Thread × 1/2" Installed Lg. (10 Each)
    7/16"-20 Thread × 5/8" Installed Lg. (10 Each)
    1/2"-20 Thread × 5/8" Installed Lg. (6 Each)
    5/8"-18 Thread × 7/8" Installed Lg. (3 Each)
    3/4"-16 Thread × 1 1/8" Installed Lg. (3 Each)
    7/8"-14 Thread × 1 1/4" Installed Lg. (3 Each)
    1"-12 Thread × 1 3/8" Installed Lg. (2 Each)
    9/16"-18 Thread × 0.813" Installed Lg. (5 Each)
    Installation Tool    		Fine
    		7/16"-14
    1/2"-13
    9/16"-12
    5/8"-11
    3/4"-16
    7/8"-14
    1 1/8"-12
    1 1/4"-12
    1 3/8"-12
    		29/64"
    33/64"
    37/64"
    45/64"
    53/64"
    1 1/16"
    1 3/16"
    1 5/16"
    X
    		0.397"
    0.453"
    0.516"
    0.578"
    0.703"
    0.828"
    1.063"
    1.186"
    1.313"    		90284A4150000000
     

    Thread-Locking Threaded Insert Assortments

    Image of Product. Front orientation. Threaded Inserts. Thread-Locking Threaded Insert Assortments.
    These assortments include various sizes of thread-locking inserts, which won’t back out or loosen from vibration. Also known as E-Z Lok, they come with Loctite® adhesive already applied, and the adhesive reaches full strength after 72 hours. After drilling and tapping your hole, install inserts with a wrench or use an installation bit (not included). 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.
    Standard Wall—Stronger than thin-wall inserts, these are your go-to choice for threading most holes.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    No. of Inserts
    Included
    Includes
    Thread
    Spacing
    For Tap Thread
    Size
    Drill Bit
    Size
    For Maximum
    Hole Diameter
    Drive
    Style
    Each
    Standard Wall
     
    18-8 Stainless Steel
    4610-32 Thread × 0.406" Installed Lg. (10 Each)
    1/4"-28 Thread × 0.438" Installed Lg. (10 Each)
    5/16"-24 Thread × 0.484" Installed Lg. (10 Each)
    3/8"-24 Thread × 0.516" Installed Lg. (10 Each)
    1/2"-20 Thread × 0.656" Installed Lg. (6 Each)    		Fine
    		3/8"-16,
    7/16"-14,
    1/2"-13,
    9/16"-12,
    3/4"-10    		5/16"
    23/64"
    27/64"
    31/64"
    21/32"    		5/16"
    23/64"
    27/64"
    31/64"
    21/32"    		Slotted
    		90247A0320000000
     
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