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    115 Products

    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.
    Medium-Strength Steel
    These Grade 5, Grade C, or Class 8 nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-207/16"5/16"SAE Grade 5
    18510095615A12000000
    1/4"-287/16"5/16"SAE Grade 5
    18510095615A1300000
    5/16"-181/2"11/32"SAE Grade 5
    18510095615A16000000
    5/16"-241/2"11/32"SAE Grade 5
    18510095615A17000000
    3/8"-169/16"29/64"SAE Grade 5
    18510095615A14000000
    3/8"-249/16"29/64"SAE Grade 5
    18510095615A15000000
    7/16"-145/8"29/64"SAE Grade 5
    18510095615A18000000
    7/16"-205/8"29/64"SAE Grade 5
    18510095615A19000000
    1/2"-133/4"19/32"SAE Grade 5
    1855095615A21000000
    1/2"-203/4"19/32"SAE Grade 5
    1855095615A22000000
    9/16"-127/8"41/64"SAE Grade 5
    1852595615A23000000
    9/16"-187/8"41/64"SAE Grade 5
    1852595615A24000000
    5/8"-1115/16"3/4"SAE Grade 5
    1852595615A25000000
    5/8"-1815/16"3/4"SAE Grade 5
    1852595615A26000000
    3/4"-101 1/16"7/8"SAE Grade 5
    1851095615A2700000
    3/4"-161 1/16"7/8"SAE Grade 5
    1851095615A2800000
    7/8"-91 1/4"63/64"SAE Grade 5
    185595615A2900000
    7/8"-141 1/4"63/64"SAE Grade 5
    185595615A31000000
    1"-81 7/16"1 3/64"SAE Grade 5
    185595615A32000000
    1"-141 7/16"1 3/64"SAE Grade 5
    185595615A33000000
    1 1/8"-71 5/8"1 11/64"SAE Grade 5
    185595615A34100000
    1 1/4"-71 13/16"1 25/64"SAE Grade 5
    185195615A35000000
    1 1/2"-62 13/64"1 39/64"SAE Grade 5
    185190640A42000000
     

    Top-Lock Distorted-Thread Locknuts

    Image of Product. Front orientation. Locknuts. Top-Lock Distorted-Thread Locknuts.
    Irregularly shaped threads at the top of these locknuts grip the screw for a stronger hold than nylon-insert locknuts. Although the threads prevent the nut from backing out due to vibration, 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. Nuts are not reusable.
    Medium-Strength Steel
    These Grade 5, Grade C, or Class 8 nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-207/16"1/4"SAE Grade 5
    10095065A150000000
    1/4"-287/16"1/4"SAE Grade 5
    5095065A10400000
    5/16"-181/2"19/64"SAE Grade 5
    5095065A16000000
    5/16"-241/2"19/64"SAE Grade 5
    5095065A10500000
    3/8"-169/16"3/8"SAE Grade 5
    5095065A17100000
    3/8"-249/16"3/8"SAE Grade 5
    5095065A10600000
    7/16"-1411/16"27/64"SAE Grade 5
    5095065A10100000
    7/16"-2011/16"27/64"SAE Grade 5
    2595065A10700000
    1/2"-133/4"1/2"SAE Grade 5
    2595065A19100000
    1/2"-203/4"1/2"SAE Grade 5
    1095065A1080000
    5/8"-1115/16"5/8"SAE Grade 5
    1095065A22000000
    5/8"-1815/16"5/8"SAE Grade 5
    1095065A1090000
    3/4"-101 1/8"3/4"SAE Grade 5
    1095065A23000000
    7/8"-91 5/16"13/16"SAE Grade 5
    595065A10200000
    7/8"-141 5/16"13/16"SAE Grade 5
    595065A11100000
    1"-81 1/2"15/16"SAE Grade 5
    595065A10300000
    1"-141 1/2"15/16"SAE Grade 5
    195065A11200000
     

    Serrated Flange Nuts

    Serrations bite into material for mild vibration resistance while the flange eliminates the need for a separate washer. These nuts are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. You can use them again and again without sacrificing strength. However, the serrations may mar the surface of your material. Also known as collar nuts.
    Medium-Strength Steel
    Image of Product. Bottom orientation. Flange Nuts. Serrated Flange Nuts.
    Rated Grade 5, Grade F, or Class 8, these nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-207/16"15/64"19/32"0.04"SAE Grade 5
    Material Certificate
    10099904A10100000
    1/4"-287/16"15/64"19/32"0.04"SAE Grade 5
    10099904A1360000
    5/16"-181/2"9/32"11/16"0.04"SAE Grade 5
    Material Certificate
    10099904A10200000
    5/16"-241/2"9/32"11/16"0.04"SAE Grade 5
    Material Certificate
    10099904A13700000
    3/8"-169/16"11/32"3/4"0.04"SAE Grade 5
    Material Certificate
    10099904A10300000
    3/8"-249/16"11/32"3/4"0.04"SAE Grade 5
    Material Certificate
    10099904A13800000
    7/16"-1411/16"3/8"59/64"0.04"SAE Grade 5
    10099904A22300000
    7/16"-2011/16"3/8"59/64"0.04"SAE Grade 5
    10099904A22400000
    1/2"-133/4"29/64"1 1/32"0.05"SAE Grade 5
    Material Certificate
    5099904A10400000
    1/2"-203/4"7/16"1"0.05"SAE Grade 5
    5099904A22500000
    5/8"-1159/64"35/64"1 1/4"0.05"SAE Grade 5
    2599904A22600000
    5/8"-1859/64"35/64"1 1/4"0.05"SAE Grade 5
    Material Certificate
    2599904A22700000
    3/4"-101 3/32"41/64"1 15/32"0.06"SAE Grade 5
    1099904A2290000
    3/4"-161 3/32"41/64"1 15/32"0.06"SAE Grade 5
    1099904A22800000
     

    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.
    Medium-Strength Steel
    These Grade 5, Grade C, or Class 8 nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    5/8"-1115/16"25/64"SAE Grade 5
    220591342A210000000
    5/8"-1815/16"25/64"SAE Grade 5
    220591342A22000000
    3/4"-101 1/16"13/32"SAE Grade 5
    220591342A23000000
    3/4"-161 1/16"13/32"SAE Grade 5
    2201091342A24000000
    7/8"-141 1/4"15/32"SAE Grade 5
    220191342A2500000
    1"-81 7/16"35/64"SAE Grade 5
    220191342A2600000
    1"-141 7/16"35/64"SAE Grade 5
    220191342A2700000
    1 1/8"-71 5/8"41/64"SAE Grade 5
    220191342A28000000
    1 1/4"-71 13/16"3/4"SAE Grade 5
    220191342A29000000
    1 1/4"-121 13/16"3/4"SAE Grade 5
    220191342A32000000
    1 1/2"-62 3/16"51/64"SAE Grade 5
    220191342A31000000
     

    Distorted-Thread Flange Nuts

    Image of Product. Bottom orientation. Flange Nuts. Distorted-Thread Flange Nuts.
    The strongest hold of all the flange nuts we offer, these have irregularly shaped threads that grip the screw to resist loosening. The threads prevent the nut from backing out due to high vibration, 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.
    Medium-Strength Steel
    Rated Grade 5, Grade F, or Class 8, these nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-207/16"15/64"9/16"0.05"SAE Grade 5
    10090426A32000000
    5/16"-181/2"9/32"11/16"0.05"SAE Grade 5
    10090426A3300000
    5/16"-241/2"9/32"11/16"0.05"SAE Grade 5
    10090426A3400000
    3/8"-169/16"11/32"3/4"0.06"SAE Grade 5
    10090426A35000000
    7/16"-1411/16"25/64"15/16"0.06"SAE Grade 5
    5090426A36000000
    7/16"-2011/16"25/64"15/16"0.06"SAE Grade 5
    5090426A37000000
    1/2"-133/4"29/64"1 1/32"0.08"SAE Grade 5
    5090426A38000000
    1/2"-203/4"29/64"1 1/32"0.08"SAE Grade 5
    5090426A39000000
    5/8"-1115/16"9/16"1 9/32"0.09"SAE Grade 5
    1090426A4100000
    3/4"-101 1/8"43/64"1 37/64"0.11"SAE Grade 5
    1090426A4200000
    7/8"-91 5/16"25/32"1 3/4"0.13"SAE Grade 5
    590426A43000000
    1"-81 1/2"29/32"2 1/16"0.13"SAE Grade 5
    190426A4400000
    1"-141 1/2"29/32"2 1/16"0.13"SAE Grade 5
    190426A4500000
     

    Locknuts for use with Cotter Pins

    Image of ProductInUse. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    Image of Product. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    Use these locknuts to secure rotating parts subjected to mild vibration, such as the wheels on carts and hand trucks. They’re not recommended for use on parts exposed to high vibration because the pin can shear under prolonged stress. These nuts are reusable, but you'll need a new cotter pin (not included) with each use.
    Medium-Strength Steel
    These Grade 5, Grade C, or Class 8 nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    For Cotter
    Pin Dia.
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-207/16"7/32"SAE Grade 5
    1/16"2597190A005000000
    1/4"-287/16"7/32"SAE Grade 5
    1/16"1097190A1100000
    5/16"-181/2"17/64"SAE Grade 5
    5/64"2597190A01000000
    3/8"-169/16"21/64"SAE Grade 5
    7/64"2597190A01500000
    3/8"-249/16"21/64"SAE Grade 5
    7/64"1097190A12000000
    7/16"-1411/16"3/8"SAE Grade 5
    7/64"2597190A02000000
    7/16"-2011/16"3/8"SAE Grade 5
    7/64"1097190A1300000
    1/2"-133/4"7/16"SAE Grade 5
    7/64"1097190A0250000
    1/2"-203/4"7/16"SAE Grade 5
    7/64"1097190A14000000
    9/16"-127/8"31/64"SAE Grade 5
    9/64"1097190A15000000
    9/16"-187/8"31/64"SAE Grade 5
    9/64"1097190A16000000
    5/8"-1115/16"35/64"SAE Grade 5
    5/32"1097190A03000000
    5/8"-1815/16"35/64"SAE Grade 5
    5/32"1097190A17000000
    3/4"-101 1/8"41/64"SAE Grade 5
    5/32"597190A03500000
    3/4"-161 1/8"41/64"SAE Grade 5
    5/32"597190A18000000
    7/8"-141 5/16"49/64"SAE Grade 5
    3/16"197190A1900000
    1"-81 1/2"55/64"SAE Grade 5
    3/16"197190A0400000
    1"-141 1/2"55/64"SAE Grade 5
    3/16"197190A2100000
    1 1/4"-71 7/8"1 3/32"SAE Grade 5
    5/16"197190A2200000
    1 1/4"-121 7/8"1 3/32"SAE Grade 5
    5/16"197190A23000000
     

    Nylon-Insert Cap Nuts

    Image of Product. Bottom orientation. Cap Nuts. Nylon-Insert Cap Nuts.
    Get the protection of a cap nut with the vibration resistance of a locknut. These nuts not only conceal protruding screw threads, they also have a nylon insert that grips the screw to prevent loosening from moderate vibration. However, the insert may become brittle if exposed to high temperatures. Nuts are reusable a handful of times, but their holding power decreases with each use.
    Medium-Strength Steel
    About twice as strong as low-strength steel, these Grade 5 nuts fasten most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Nylon 6/6 Cap—The nylon cap on these nuts is softer than metal, so it's less likely to scratch surrounding surfaces or parts.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel with Nylon 6/6 Cap
    3/8"-2421/64"9/16"5/8"SAE Grade 5
    2501098190A270000000
     

    Steel Serrated-Flange Thread-Locking Hex Head Screws

    Image of Product. Front orientation. Hex Head Screws. Steel Serrated-Flange Thread-Locking Hex Head Screws.
    Image of Product. Back orientation. Hex Head Screws. Steel Serrated-Flange Thread-Locking Hex Head Screws.
    Dual protection to prevent loosening from vibration. These screws have a flange with a serrated edge to grip material while an acrylic adhesive seals the threads together permanently once installed. The head's six flat sides keep wrenches and sockets from slipping and rounding off the drive.
    Head height includes the flange. Length is measured from under the flange.
    Medium-Strength Fastener—Your go-to screws for fastening most machinery and equipment. They have tensile strengths from 90,000 to 120,000 psi.
    Zinc-Plated Steel—A common choice for areas with occasional exposure to moisture.
    Head
    Threadlocker
    Lg.
    Wd.
    Ht.
    Flange
    Dia.
    Type
    Temp.,
    ° F
    Threading
    Thread
    Spacing
    Fastener Strength
    Grade/Class
    Tensile Strength,
    psi
    Pkg.
    Qty.
    Pkg.
    Medium-Strength Zinc-Plated Steel
     
    1/4"-20
    1/2"3/8"9/32"9/16"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,0001094440A11000000
    1"3/8"9/32"9/16"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,0001094440A12000000
    1 1/2"3/8"9/32"9/16"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,0001094440A13000000
    2"3/8"9/32"9/16"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,0001094440A14000000
     
    5/16"-18
    3/4"1/2"21/64"11/16"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,0001094440A15000000
    1"1/2"21/64"11/16"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,000594440A1600000
    1 1/2"1/2"21/64"11/16"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,000594440A1700000
    2"1/2"21/64"11/16"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,000594440A1800000
     
    3/8"-16
    3/4"9/16"25/64"13/16"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,000594440A1900000
    1"9/16"25/64"13/16"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,000594440A2100000
    1 1/2"9/16"25/64"13/16"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,000594440A2200000
    2"9/16"25/64"13/16"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,000594440A2300000
     
    1/2"-13
    1"3/4"33/64"1 5/64"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,000194440A2400000
    1 1/2"3/4"33/64"1 5/64"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,000194440A2500000
    2"3/4"33/64"1 5/64"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,000194440A2600000
    3"3/4"33/64"1 5/64"Acrylic Adhesive-65 to 300Fully ThreadedCoarseSAE Grade 5
    110,000194440A2700000
     
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