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    15 Products

    Nylon-Insert Locknuts
    3D CAD models available

    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.
    High-Strength Steel
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc Yellow-Chromate-Plated Steel—With a more durable finish than clear zinc plating, these nuts are suitable for most wet and outdoor environments. However, they won't hold up to the harsh chemicals that stainless steel can.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Steel—These locknuts are best for dry environments since moisture will cause them to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert
    Max.
    Temp.
    Pkg.
    Qty.
    Pkg.
    Zinc Yellow-Chromate-Plated Steel
    1 1/4"-12
    1 13/16"1 25/64"SAE Grade 8
    220° F1000000000000000
     
    Black-Oxide Steel
    1 1/4"-12
    1 13/16"1 25/64"SAE Grade 8
    220° F100000000000000
     
    Steel
    1 1/4"-12
    1 13/16"1 25/64"SAE Grade 8
    220° F100000000000000
     

    Thin-Profile Nylon-Insert Locknuts
    3D CAD models available

    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.
    High-Strength Steel
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc Yellow-Chromate-Plated Steel—With a more durable finish than clear zinc plating, these nuts are suitable for most wet and outdoor environments. However, they won't hold up to the harsh chemicals that stainless steel can.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp.
    Pkg.
    Qty.
    Pkg.
    Zinc Yellow-Chromate-Plated Steel
    1 1/4"-12
    1 13/16"3/4"SAE Grade 8
    Not Rated1000000000000000
     
    Black-Oxide Steel
    1 1/4"-12
    1 13/16"47/64"SAE Grade 8
    250° F100000000000000
     
    Medium-Strength Steel
    These Grade 5 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.
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1 1/4"-12
    1 13/16"3/4"SAE Grade 5
    220° F1000000000000000
     
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength 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.
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1 1/4"-12
    1 13/16"3/4"220° F100000000000000
     
    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.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1 1/4"-12
    1 13/16"3/4"220° F1000000000000000
     

    Thin-Heavy-Profile Nylon-Insert Locknuts
    3D CAD models available

    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile Nylon-Insert Locknuts.
    About half the height of standard-profile locknuts and 10% wider, these fit in spaces with low clearance and handle heavier loads by distributing them over a larger area. 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.
    High-Strength Steel
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Black Phosphate-Coated Steel—The dark coating creates both a finished appearance and a barrier against rust that's comparable to zinc yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert
    Max.
    Temp.
    Each
    Black Phosphate-Coated Steel
    1 1/4"-12
    2"1 7/64"ASTM Grade C
    250° F00000000000000
     

    Top-Lock Distorted-Thread Locknuts
    3D CAD models available

    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.
    High-Strength Steel
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength nuts. 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 1/4"-12
    1 7/8"1 3/32"ASTM Grade C
    100000000000000
     

    Locknuts for use with Cotter Pins
    3D CAD models available

    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
    Image of ProductInUse. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    Image of Product. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    These Grade 5 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 1/4"-12
    1 7/8"1 3/32"SAE Grade 5
    5/16"1000000000000000
     
    Low-Strength Steel
    Image of ProductInUse. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    Image of Product. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength 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.
    For Cotter
    Pin Dia.
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1 1/4"-12
    1 7/8"1 1/16"9/32"100000000000000
     

    Thin-Profile Flex-Top Locknuts for Heavy Vibration
    3D CAD models available

    About two-thirds the height of standard flex-top nuts, 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 top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use 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.
    Steel
    Image of Product. Front orientation. Locknuts. Thin-Profile Flex-Top Locknuts for Heavy Vibration.
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc yellow-chromate plating.
    Steel—These locknuts are best for dry environments since moisture will cause them to rust.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    1 1/4"-12
    1 13/16"49/64"1000000000000000
     
    Steel
    1 1/4"-12
    1 13/16"49/64"100000000000000
     

    Thin-Profile Steel-Insert Locknuts for Extreme Vibration
    3D CAD models available

    Image of Product. Bottom orientation. Locknuts. Thin-Profile Steel-Insert Locknuts for Extreme Vibration.
    About two-thirds the height of standard steel-insert locknuts, these fit in spaces with low clearance and offer the most secure hold of all our thin-profile locknuts. You can also use them as jam nuts by threading them against a hex nut to hold it in place. The tab on the insert stops the nut from rotating, even under extreme vibration. These locknuts are ideal for equipment with constant motion or jarring starts and stops, including conveyors, shakers, and compactors. You can even reuse them once or twice, but their holding power decreases with each use.
    High-Strength Steel
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Steel—These locknuts are best for dry environments since moisture will cause them to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Each
    Steel
    1 1/4"-12
    1 7/8"7/8"SAE Grade 8
    000000000000000
     
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