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    128 Products

    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.
    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.
    Each
    Black Phosphate-Coated Steel
    1 1/4"-12
    2"1 7/64"ASTM Grade C
    250° F00000000000000
    1 1/2"-12
    2 3/8"1 5/16"ASTM Grade C
    250° F0000000000000
    1 3/4"-12
    2 3/4"1 15/32"ASTM Grade C
    250° F00000000000000
    2"-12
    3 1/8"1 43/64"ASTM Grade C
    250° F00000000000000
    2 1/4"-12
    3 1/2"1 15/16"ASTM Grade C
    250° F00000000000000
    2 1/2"-12
    4"2 3/16"ASTM Grade C
    250° F00000000000000
    2 3/4"-12
    4"2 3/16"ASTM Grade C
    250° F00000000000000
    3"-12
    4 1/2"2 41/64"ASTM Grade C
    250° F000000000000000
     
    Steel
    1 1/8"-12
    1 7/8"1"ASTM Grade C
    250° F00000000000000
    1 3/8"-12
    2 13/64"1 3/16"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 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.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    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.
    Zinc Flake-Coated Steel—The most durable zinc coating, these locknuts have a multilayer finish that resists wear for long-term rust protection. However, similar to zinc yellow-chromate-plated nuts, they won't hold up to harsh chemicals like stainless steel can.
    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.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc Yellow-Chromate-Plated Steel
    1/4"-20
    7/16"7/32"ASTM Grade C
    5000000000000000
    1/4"-28
    7/16"7/32"ASTM Grade C
    500000000000000
    5/16"-18
    1/2"17/64"ASTM Grade C
    5000000000000000
    5/16"-24
    1/2"17/64"ASTM Grade C
    5000000000000000
    3/8"-16
    9/16"21/64"ASTM Grade C
    250000000000000
    3/8"-24
    9/16"21/64"ASTM Grade C
    250000000000000
    7/16"-14
    11/16"3/8"ASTM Grade C
    2500000000000000
    7/16"-20
    11/16"3/8"ASTM Grade C
    2500000000000000
    1/2"-13
    3/4"7/16"ASTM Grade C
    100000000000000
    1/2"-20
    3/4"7/16"ASTM Grade C
    100000000000000
    9/16"-12
    7/8"31/64"ASTM Grade C
    1000000000000000
    9/16"-18
    7/8"31/64"ASTM Grade C
    1000000000000000
    5/8"-11
    15/16"35/64"ASTM Grade C
    50000000000000
    5/8"-18
    15/16"35/64"ASTM Grade C
    50000000000000
    3/4"-10
    1 1/8"41/64"ASTM Grade C
    500000000000000
    3/4"-16
    1 1/8"41/64"ASTM Grade C
    500000000000000
    7/8"-9
    1 5/16"3/4"ASTM Grade C
    10000000000000
    7/8"-14
    1 5/16"3/4"ASTM Grade C
    10000000000000
    1"-8
    1 1/2"55/64"ASTM Grade C
    10000000000000
    1"-14
    1 1/2"55/64"ASTM Grade C
    10000000000000
     
    Zinc-Plated Steel
    1/4"-20
    7/16"7/32"ASTM Grade C
    1000000000000000
    1/4"-28
    7/16"7/32"ASTM Grade C
    10000000000000000
    5/16"-18
    1/2"17/64"ASTM Grade C
    10000000000000000
    5/16"-24
    1/2"17/64"ASTM Grade C
    10000000000000000
    3/8"-16
    9/16"21/64"ASTM Grade C
    10000000000000000
    3/8"-24
    9/16"21/64"ASTM Grade C
    10000000000000000
    7/16"-14
    11/16"3/8"ASTM Grade C
    5000000000000000
    7/16"-20
    11/16"3/8"ASTM Grade C
    5000000000000000
    1/2"-13
    3/4"7/16"ASTM Grade C
    5000000000000000
    1/2"-20
    3/4"7/16"ASTM Grade C
    5000000000000000
    9/16"-12
    7/8"31/64"ASTM Grade C
    2500000000000000
    9/16"-18
    7/8"31/64"ASTM Grade C
    2500000000000000
    5/8"-11
    15/16"35/64"ASTM Grade C
    2500000000000000
    5/8"-18
    15/16"35/64"ASTM Grade C
    2500000000000000
    3/4"-10
    1 1/8"41/64"ASTM Grade C
    100000000000000
    3/4"-16
    1 1/8"41/64"ASTM Grade C
    100000000000000
    7/8"-9
    1 5/16"3/4"ASTM Grade C
    1000000000000000
    7/8"-14
    1 5/16"3/4"ASTM Grade C
    1000000000000000
    1"-8
    1 1/2"55/64"ASTM Grade C
    500000000000000
    1"-14
    1 1/2"55/64"ASTM Grade C
    500000000000000
    1 1/8"-7
    1 11/16"1"ASTM Grade C
    10000000000000
    1 1/8"-12
    1 11/16"1"ASTM Grade C
    10000000000000
    1 1/4"-7
    1 7/8"1 3/32"ASTM Grade C
    10000000000000
    1 1/4"-12
    1 7/8"1 3/32"ASTM Grade C
    10000000000000
    1 1/2"-6
    2 1/4"1 5/16"ASTM Grade C
    10000000000000
    1 1/2"-12
    2 1/4"1 5/16"ASTM Grade C
    10000000000000
     
    Black-Oxide Steel
    1/4"-20
    7/16"7/32"ASTM Grade C
    5000000000000000
    5/16"-18
    1/2"17/64"ASTM Grade C
    5000000000000000
    5/16"-24
    1/2"17/64"ASTM Grade C
    5000000000000000
    3/8"-16
    9/16"21/64"ASTM Grade C
    2500000000000000
    3/8"-24
    9/16"21/64"ASTM Grade C
    2500000000000000
    7/16"-14
    11/16"3/8"ASTM Grade C
    100000000000000
    7/16"-20
    11/16"3/8"ASTM Grade C
    100000000000000
    1/2"-13
    3/4"7/16"ASTM Grade C
    1000000000000000
    1/2"-20
    3/4"7/16"ASTM Grade C
    1000000000000000
    9/16"-12
    7/8"31/64"ASTM Grade C
    1000000000000000
    9/16"-18
    7/8"31/64"ASTM Grade C
    1000000000000000
    5/8"-11
    15/16"35/64"ASTM Grade C
    500000000000000
    5/8"-18
    15/16"35/64"ASTM Grade C
    500000000000000
    3/4"-10
    1 1/8"41/64"ASTM Grade C
    500000000000000
    3/4"-16
    1 1/8"41/64"ASTM Grade C
    500000000000000
    7/8"-9
    1 5/16"3/4"ASTM Grade C
    10000000000000
    7/8"-14
    1 5/16"3/4"ASTM Grade C
    10000000000000
    1"-8
    1 1/2"55/64"ASTM Grade C
    10000000000000
     
    Zinc Flake-Coated Steel
    1/4"-20
    7/16"7/32"ASTM Grade C
    2500000000000000
    1/4"-28
    7/16"7/32"ASTM Grade C
    2500000000000000
    5/16"-18
    1/2"17/64"ASTM Grade C
    100000000000000
    5/16"-24
    1/2"17/64"ASTM Grade C
    100000000000000
    3/8"-16
    9/16"21/64"ASTM Grade C
    1000000000000000
    3/8"-24
    9/16"21/64"ASTM Grade C
    1000000000000000
    7/16"-14
    11/16"3/8"ASTM Grade C
    500000000000000
    7/16"-20
    11/16"3/8"ASTM Grade C
    500000000000000
    1/2"-13
    3/4"7/16"ASTM Grade C
    500000000000000
    1/2"-20
    3/4"7/16"ASTM Grade C
    500000000000000
    9/16"-18
    7/8"31/64"ASTM Grade C
    10000000000000
    5/8"-11
    15/16"35/64"ASTM Grade C
    10000000000000
    5/8"-18
    15/16"35/64"ASTM Grade C
    10000000000000
    3/4"-10
    1 1/8"41/64"ASTM Grade C
    10000000000000
    3/4"-16
    1 1/8"41/64"ASTM Grade C
    10000000000000
    1"-8
    1 1/2"55/64"ASTM Grade C
    100000000000000
     
    Cadmium-Plated Steel
    1/4"-20
    7/16"7/32"ASTM Grade C
    10000000000000000
    1/4"-28
    7/16"7/32"ASTM Grade C
    10000000000000000
    5/16"-18
    1/2"17/64"ASTM Grade C
    10000000000000000
    5/16"-24
    1/2"17/64"ASTM Grade C
    10000000000000000
    3/8"-16
    9/16"21/64"ASTM Grade C
    10000000000000000
    3/8"-24
    9/16"21/64"ASTM Grade C
    500000000000000
    7/16"-14
    11/16"3/8"ASTM Grade C
    5000000000000000
    7/16"-20
    11/16"3/8"ASTM Grade C
    5000000000000000
    1/2"-13
    3/4"7/16"ASTM Grade C
    5000000000000000
    1/2"-20
    3/4"7/16"ASTM Grade C
    5000000000000000
    9/16"-12
    7/8"31/64"ASTM Grade C
    2500000000000000
    9/16"-18
    7/8"31/64"ASTM Grade C
    2500000000000000
    5/8"-11
    15/16"35/64"ASTM Grade C
    2500000000000000
    5/8"-18
    15/16"35/64"ASTM Grade C
    2500000000000000
    3/4"-10
    1 1/8"41/64"ASTM Grade C
    1000000000000000
    3/4"-16
    1 1/8"41/64"ASTM Grade C
    1000000000000000
    7/8"-9
    1 5/16"3/4"ASTM Grade C
    1000000000000000
    7/8"-14
    1 5/16"3/4"ASTM Grade C
    50000000000000
    1"-8
    1 1/2"55/64"ASTM Grade C
    500000000000000
    1"-14
    1 1/2"55/64"ASTM Grade C
    500000000000000
     
    Steel
    1/4"-20
    7/16"7/32"ASTM Grade C
    1000000000000000
    1/4"-28
    7/16"7/32"ASTM Grade C
    1000000000000000
    5/16"-18
    1/2"17/64"ASTM Grade C
    1000000000000000
    5/16"-24
    1/2"17/64"ASTM Grade C
    1000000000000000
    3/8"-16
    9/16"21/64"ASTM Grade C
    10000000000000000
    3/8"-24
    9/16"21/64"ASTM Grade C
    10000000000000000
    7/16"-14
    11/16"3/8"ASTM Grade C
    5000000000000000
    7/16"-20
    11/16"3/8"ASTM Grade C
    5000000000000000
    1/2"-13
    3/4"7/16"ASTM Grade C
    5000000000000000
    1/2"-20
    3/4"7/16"ASTM Grade C
    5000000000000000
    9/16"-12
    7/8"31/64"ASTM Grade C
    2500000000000000
    9/16"-18
    7/8"31/64"ASTM Grade C
    2500000000000000
    5/8"-11
    15/16"35/64"ASTM Grade C
    2500000000000000
    5/8"-18
    15/16"35/64"ASTM Grade C
    2500000000000000
    3/4"-10
    1 1/8"41/64"ASTM Grade C
    100000000000000
    3/4"-16
    1 1/8"41/64"ASTM Grade C
    100000000000000
    7/8"-14
    1 5/16"3/4"ASTM Grade C
    1000000000000000
    1"-8
    1 1/2"55/64"ASTM Grade C
    500000000000000
     
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