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    179 Products

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

    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
    Image of Product. Front orientation. Locknuts. Thin-Profile Nylon-Insert Locknuts.
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength steel 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.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc Yellow-Chromate-Plated Steel
    1/4"-20
    7/16"13/64"SAE Grade 8
    Not Rated10000000000000000
    5/16"-18
    1/2"1/4"SAE Grade 8
    Not Rated10000000000000000
    3/8"-16
    9/16"17/64"SAE Grade 8
    Not Rated10000000000000000
    3/8"-24
    9/16"17/64"SAE Grade 8
    Not Rated5000000000000000
    7/16"-14
    5/8"5/16"SAE Grade 8
    Not Rated250000000000000
    7/16"-20
    5/8"5/16"SAE Grade 8
    Not Rated250000000000000
    1/2"-13
    3/4"5/16"SAE Grade 8
    Not Rated2500000000000000
    5/8"-11
    15/16"25/64"SAE Grade 8
    Not Rated100000000000000
    1 1/4"-12
    1 13/16"3/4"SAE Grade 8
    Not Rated100000000000000
    1 1/2"-12
    2 3/16"51/64"SAE Grade 8
    Not Rated100000000000000
     
    Zinc-Plated Steel
    5/16"-24
    1/2"1/4"SAE Grade 8
    2201000000000000000
    1/2"-20
    3/4"5/16"SAE Grade 8
    22050000000000000
    5/8"-18
    15/16"25/64"SAE Grade 8
    220500000000000000
    3/4"-16
    1 1/16"13/32"SAE Grade 8
    22010000000000000
    7/8"-14
    1 1/4"15/32"SAE Grade 8
    22010000000000000
    1"-14
    1 7/16"35/64"SAE Grade 8
    22010000000000000
    1 1/8"-12
    1 53/64"41/64"SAE Grade 8
    220100000000000000
     
    Medium-Strength Steel
    Image of Product. Front orientation. Locknuts. Thin-Profile Nylon-Insert Locknuts.
    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., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    5/8"-11
    15/16"25/64"SAE Grade 5
    2205000000000000000
    5/8"-18
    15/16"25/64"SAE Grade 5
    220500000000000000
    3/4"-10
    1 1/16"13/32"SAE Grade 5
    220500000000000000
    3/4"-16
    1 1/16"13/32"SAE Grade 5
    2201000000000000000
    7/8"-14
    1 1/4"15/32"SAE Grade 5
    22010000000000000
    1"-8
    1 7/16"35/64"SAE Grade 5
    22010000000000000
    1"-14
    1 7/16"35/64"SAE Grade 5
    22010000000000000
    1 1/8"-7
    1 5/8"41/64"SAE Grade 5
    220100000000000000
    1 1/4"-7
    1 13/16"3/4"SAE Grade 5
    220100000000000000
    1 1/4"-12
    1 13/16"3/4"SAE Grade 5
    220100000000000000
    1 1/2"-6
    2 3/16"51/64"SAE Grade 5
    220100000000000000
     
    Low-Strength Steel
    Image of Product. Front orientation. Locknuts. Thin-Profile Nylon-Insert Locknuts.
    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.
    Black Zinc-Plated Steel—The dark zinc plating withstands occasional exposure to moisture while creating a finished look.
    Black Corrosion-Resistant-Coated Steel—These nuts combine a finished appearance with the rust resistance of stainless steel. The coating has been tested to extreme standards, including 1,000 hours of salt spray resistance, to hold up in wet and outdoor environments. Also known as black luster.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    2-56
    1/4"7/64"220100000000000000000
    4-40
    1/4"7/64"2201000000000000000
    5-40
    1/4"7/64"2201000000000000000
    6-32
    5/16"1/8"22010000000000000000
    8-32
    11/32"11/64"2201000000000000000
    10-24
    3/8"11/64"2201000000000000000
    10-32
    3/8"11/64"2201000000000000000
    12-24
    7/16"13/64"2201000000000000000
    1/4"-20
    7/16"13/64"2201000000000000000
    1/4"-28
    7/16"13/64"2201000000000000000
    5/16"-18
    1/2"1/4"2201000000000000000
    5/16"-24
    1/2"1/4"2201000000000000000
    3/8"-16
    9/16"17/64"2201000000000000000
    3/8"-24
    9/16"17/64"2201000000000000000
    7/16"-14
    5/8"5/16"2201000000000000000
    7/16"-20
    5/8"5/16"22010000000000000000
    1/2"-13
    3/4"5/16"22010000000000000000
    1/2"-20
    3/4"5/16"22010000000000000000
    9/16"-12
    7/8"23/64"22010000000000000000
    9/16"-18
    7/8"23/64"22010000000000000000
    5/8"-11
    15/16"25/64"2205000000000000000
    5/8"-18
    15/16"25/64"2205000000000000000
    3/4"-10
    1 1/16"13/32"220100000000000000
    3/4"-16
    1 1/16"13/32"220100000000000000
    7/8"-9
    1 1/4"15/32"22050000000000000
    7/8"-14
    1 1/4"15/32"22050000000000000
    1"-8
    1 7/16"35/64"22010000000000000
    1"-14
    1 7/16"35/64"22010000000000000
    1 1/8"-7
    1 5/8"41/64"22010000000000000
    1 1/4"-7
    1 13/16"3/4"22010000000000000
    1 1/4"-12
    1 13/16"3/4"22010000000000000
    1 3/8"-6
    2"51/64"22010000000000000
    1 1/2"-6
    2 3/16"51/64"22010000000000000
     
    Black Zinc-Plated Steel
    6-32
    5/16"1/8"220250000000000000
    8-32
    11/32"11/64"220250000000000000
    10-24
    3/8"11/64"220250000000000000
    10-32
    3/8"11/64"220250000000000000
    12-24
    7/16"13/64"220250000000000000
    1/4"-20
    7/16"13/64"220250000000000000
    5/16"-18
    1/2"1/4"220100000000000000
    3/8"-16
    9/16"17/64"220100000000000000
     
    Black Corrosion-Resistant-Coated Steel
    6-32
    5/16"1/8"22050000000000000
    8-32
    11/32"11/64"22050000000000000
    10-24
    3/8"11/64"22050000000000000
    10-32
    3/8"11/64"22050000000000000
    1/4"-20
    7/16"13/64"22050000000000000
    5/16"-18
    1/2"1/4"22050000000000000
    3/8"-16
    9/16"17/64"22050000000000000
    1/2"-13
    3/4"5/16"22050000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Locknuts. Thin-Profile 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.
    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.
    316 Stainless Steel—Our most corrosion-resistant nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    4-40
    1/4"7/64"2205000000000000000
    6-32
    5/16"1/8"2201000000000000000
    8-32
    11/32"11/64"2201000000000000000
    10-24
    3/8"11/64"2201000000000000000
    10-32
    3/8"11/64"220500000000000000
    1/4"-20
    7/16"13/64"220500000000000000
    1/4"-28
    7/16"13/64"220500000000000000
    5/16"-18
    1/2"1/4"220500000000000000
    5/16"-24
    1/2"1/4"220500000000000000
    3/8"-16
    9/16"17/64"220250000000000000
    3/8"-24
    9/16"17/64"220250000000000000
    7/16"-14
    5/8"5/16"220100000000000000
    7/16"-20
    5/8"5/16"22050000000000000
    1/2"-13
    3/4"5/16"220100000000000000
    1/2"-20
    3/4"5/16"22050000000000000
    9/16"-18
    7/8"23/64"220100000000000000
    5/8"-11
    15/16"25/64"22010000000000000
    5/8"-18
    15/16"25/64"22010000000000000
    3/4"-10
    1 1/16"13/32"22010000000000000
    3/4"-16
    1 1/16"13/32"220100000000000000
    7/8"-9
    1 1/4"15/32"22010000000000000
    7/8"-14
    1 1/4"15/32"220100000000000000
    1"-8
    1 7/16"35/64"220100000000000000
    1"-14
    1 7/16"35/64"220100000000000000
    1 1/8"-7
    1 5/8"41/64"220100000000000000
    1 1/4"-7
    1 13/16"3/4"220100000000000000
    1 1/4"-12
    1 13/16"3/4"220100000000000000
    1 1/2"-6
    2 3/16"51/64"220100000000000000
     
    Black-Oxide 18-8 Stainless Steel
    4-40
    1/4"1/8"22010000000000000000
    6-32
    5/16"9/64"22010000000000000000
    8-32
    11/32"3/16"22010000000000000000
    10-24
    3/8"3/16"22010000000000000000
    10-32
    3/8"3/16"22010000000000000000
    1/4"-20
    7/16"13/64"2205000000000000000
    5/16"-18
    1/2"1/4"2205000000000000000
    3/8"-16
    9/16"17/64"2205000000000000000
    3/8"-24
    9/16"17/64"2205000000000000000
    1/2"-13
    3/4"5/16"22050000000000000
    1/2"-20
    3/4"5/16"22050000000000000
     
    316 Stainless Steel
    10-24
    3/8"11/64"2205000000000000000
    10-32
    3/8"11/64"2205000000000000000
    1/4"-20
    7/16"13/64"220250000000000000
    1/4"-28
    7/16"13/64"2205000000000000000
    5/16"-18
    1/2"1/4"220250000000000000
    5/16"-24
    1/2"1/4"2205000000000000000
    3/8"-16
    9/16"17/64"2202500000000000000
    3/8"-24
    9/16"17/64"2202500000000000000
    7/16"-14
    5/8"5/16"2202500000000000000
    7/16"-20
    5/8"5/16"2202500000000000000
    1/2"-13
    3/4"5/16"2201000000000000000
    1/2"-20
    3/4"5/16"2201000000000000000
    3/4"-10
    1 1/16"25/64"220100000000000000
     

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

    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
    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile Nylon-Insert Locknuts.
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength steel 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—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Each
    Black Phosphate-Coated Steel
    1 1/4"-12
    2"1 7/64"ASTM Grade C
    25000000000000000
    1 1/2"-12
    2 3/8"1 5/16"ASTM Grade C
    25000000000000000
    1 3/4"-12
    2 3/4"1 15/32"ASTM Grade C
    25000000000000000
    2"-12
    3 1/8"1 43/64"ASTM Grade C
    25000000000000000
    2 1/4"-12
    3 1/2"1 15/16"ASTM Grade C
    25000000000000000
    2 1/2"-12
    4"2 3/16"ASTM Grade C
    25000000000000000
    2 3/4"-12
    4"2 3/16"ASTM Grade C
    25000000000000000
    3"-12
    4 1/2"2 41/64"ASTM Grade C
    250000000000000000
     
    Steel
    1 1/8"-12
    1 7/8"1"ASTM Grade C
    25000000000000000
    1 3/8"-12
    2 13/64"1 3/16"ASTM Grade C
    25000000000000000
     
    Low-Strength Steel
    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile Nylon-Insert Locknuts.
    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.
    Black Corrosion-Resistant-Coated Steel—These nuts combine a finished appearance with the rust resistance of stainless steel. The coating has been tested to extreme standards, including 1,000 hours of salt spray resistance, to hold up in wet and outdoor environments. Also known as black luster.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    1/2"9/32"250100000000000000000
    5/16"-18
    9/16"5/16"25010000000000000000
    3/8"-16
    11/16"13/32"2505000000000000000
    1/2"-13
    7/8"17/32"2502500000000000000
    5/8"-11
    1 1/16"39/64"2501000000000000000
    3/4"-10
    1 1/4"45/64"2501000000000000000
    1"-8
    1 5/8"57/64"25010000000000000
    1 1/4"-7
    2"1 7/64"25010000000000000
     
    Black Corrosion-Resistant-Coated Steel
    1/4"-20
    1/2"9/32"25050000000000000
    5/16"-18
    9/16"5/16"25050000000000000
    3/8"-16
    11/16"13/32"25010000000000000
    1/2"-13
    7/8"17/32"25010000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile 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.
    316 Stainless Steel—Our most corrosion-resistant nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/4"-20
    1/2"9/32"25025000000000000000
    5/16"-18
    9/16"5/16"2502000000000000000
    3/8"-16
    11/16"13/32"2501000000000000000
    1/2"-13
    7/8"17/32"25010000000000000
    5/8"-11
    1 1/16"5/8"25010000000000000
    3/4"-10
    1 1/4"45/64"250100000000000000
    1"-8
    1 5/8"59/64"250100000000000000
     
    316 Stainless Steel
    3/8"-16
    11/16"13/32"25010000000000000
    1/2"-13
    7/8"17/32"25010000000000000
    5/8"-11
    1 1/16"39/64"25010000000000000
    3/4"-10
    1 1/4"45/64"250100000000000000
     

    Mil. Spec. Thin-Profile Nylon-Insert Locknuts
    3D CAD models available

    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.
    Low-Strength Steel
    Image of Product. Front orientation. Locknuts. Mil. Spec. Thin-Profile Nylon-Insert Locknuts.
    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.
    Cadmium Yellow-Chromate-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.
    Thread
    Size
    Wd.
    Ht.
    Mil.
    Spec.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    4-40
    1/4"1/8"MS21083N04250NASM2108310000000000000000
    6-32
    5/16"9/64"MS21083N06250NASM210831000000000000000
    8-32
    11/32"3/16"MS21083N08250NASM21083100000000000000
    10-32
    3/8"3/16"MS21083N3250NASM21083100000000000000
    1/4"-28
    7/16"7/32"MS21083N4250NASM21083100000000000000
    1/2"-20
    3/4"5/16"MS21083N8250NASM2108310000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Locknuts. Mil. Spec. Thin-Profile 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"7/64"MS21083C02250NASM210835000000000000000
    4-40
    1/4"1/8"MS21083C04250NASM210831000000000000000
    6-32
    5/16"9/64"MS21083C06250NASM210831000000000000000
    8-32
    11/32"3/16"MS21083C08250NASM2108350000000000000
    10-32
    3/8"3/16"MS21083C3250NASM21083500000000000000
    1/4"-28
    7/16"7/32"MS21083C4250NASM21083500000000000000
    5/16"-24
    1/2"17/64"MS21083C5250NASM2108310000000000000
    3/8"-24
    9/16"9/32"MS21083C6250NASM2108310000000000000
    7/16"-20
    11/16"21/64"MS21083C7250NASM21083100000000000000
    1/2"-20
    3/4"5/16"MS21083C8250NASM2108310000000000000
    5/8"-18
    15/16"13/32"MS21083C10250NASM21083100000000000000
     
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