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    1,602 Products

    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.
    High-Strength Steel
    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.
    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., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Yellow-Chromate-Plated Steel
    1/4"-20
    7/16"13/64"SAE Grade 8
    Not Rated10094945A205000000
    1/4"-28
    7/16"13/64"SAE Grade 8
    2501094945A1390000
    5/16"-18
    1/2"1/4"SAE Grade 8
    Not Rated10094945A21300000
    5/16"-24
    1/2"1/4"SAE Grade 8
    2501094945A11900000
    3/8"-16
    9/16"17/64"SAE Grade 8
    Not Rated10094945A21700000
    3/8"-24
    9/16"17/64"SAE Grade 8
    Not Rated5094945A21800000
    7/16"-14
    5/8"5/16"SAE Grade 8
    Not Rated2594945A26000000
    7/16"-20
    5/8"5/16"SAE Grade 8
    Not Rated2594945A27000000
    1/2"-13
    3/4"5/16"SAE Grade 8
    Not Rated2594945A22400000
    1/2"-20
    3/4"5/16"SAE Grade 8
    250594945A1210000
    5/8"-11
    15/16"25/64"SAE Grade 8
    Not Rated1094945A2270000
    5/8"-18
    15/16"25/64"SAE Grade 8
    250594945A1220000
    3/4"-16
    1 1/16"13/32"SAE Grade 8
    250194945A1230000
    7/8"-14
    1 1/4"15/32"SAE Grade 8
    250194945A1240000
    1"-14
    1 7/16"35/64"SAE Grade 8
    250194945A1250000
    1 1/4"-12
    1 13/16"3/4"SAE Grade 8
    Not Rated194945A28000000
    1 1/2"-12
    2 3/16"51/64"SAE Grade 8
    Not Rated194945A29000000
     
    Zinc-Plated Steel
    5/16"-24
    1/2"1/4"SAE Grade 8
    2201094945A2150000
    1/2"-20
    3/4"5/16"SAE Grade 8
    220594945A2250000
    5/8"-18
    15/16"25/64"SAE Grade 8
    220594945A2300000
    3/4"-16
    1 1/16"13/32"SAE Grade 8
    220194945A2350000
    7/8"-14
    1 1/4"15/32"SAE Grade 8
    220194945A2400000
    1"-14
    1 7/16"35/64"SAE Grade 8
    220194945A2500000
    1 1/8"-12
    1 53/64"41/64"SAE Grade 8
    220194945A25100000
     
    Black-Oxide Steel
    1/4"-20
    7/16"13/64"SAE Grade 8
    2502594945A13100000
    1/4"-28
    7/16"13/64"SAE Grade 8
    2501094945A13200000
    5/16"-18
    1/2"1/4"SAE Grade 8
    2502594945A13300000
    5/16"-24
    1/2"1/4"SAE Grade 8
    2501094945A11100000
    3/8"-16
    9/16"17/64"SAE Grade 8
    2501094945A1340000
    3/8"-24
    9/16"17/64"SAE Grade 8
    2501094945A1350000
    7/16"-20
    5/8"5/16"SAE Grade 8
    2501094945A13600000
    1/2"-13
    3/4"5/16"SAE Grade 8
    2501094945A13700000
    1/2"-20
    3/4"5/16"SAE Grade 8
    250594945A1120000
    5/8"-11
    15/16"25/64"SAE Grade 8
    250594945A13800000
    5/8"-18
    15/16"25/64"SAE Grade 8
    250594945A11300000
    3/4"-16
    1 1/16"13/32"SAE Grade 8
    250194945A1140000
    7/8"-14
    1 1/4"15/32"SAE Grade 8
    250194945A1150000
    1"-14
    1 7/16"35/64"SAE Grade 8
    250194945A1160000
    1 1/4"-12
    1 13/16"47/64"SAE Grade 8
    250194945A11800000
    1 1/2"-12
    2 11/64"51/64"SAE Grade 8
    250194945A11700000
     
    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., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    5/8"-11
    15/16"25/64"SAE Grade 5
    220591342A210000000
    5/8"-18
    15/16"25/64"SAE Grade 5
    220591342A22000000
    3/4"-10
    1 1/16"13/32"SAE Grade 5
    220591342A23000000
    3/4"-16
    1 1/16"13/32"SAE Grade 5
    2201091342A24000000
    7/8"-14
    1 1/4"15/32"SAE Grade 5
    220191342A2500000
    1"-8
    1 7/16"35/64"SAE Grade 5
    220191342A2600000
    1"-14
    1 7/16"35/64"SAE Grade 5
    220191342A2700000
    1 1/8"-7
    1 5/8"41/64"SAE Grade 5
    220191342A28000000
    1 1/4"-7
    1 13/16"3/4"SAE Grade 5
    220191342A29000000
    1 1/4"-12
    1 13/16"3/4"SAE Grade 5
    220191342A32000000
    1 1/2"-6
    2 3/16"51/64"SAE Grade 5
    220191342A31000000
     
    Low-Strength Steel
    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
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    2-56
    1/4"7/64"22010090633A004000000
    4-40
    1/4"7/64"22010090633A0050000
    5-40
    1/4"7/64"22010090633A0060000
    6-32
    5/16"1/8"22010090633A00700000
    8-32
    11/32"11/64"22010090633A0090000
    10-24
    3/8"11/64"22010090633A0110000
    10-32
    3/8"11/64"22010090633A4110000
    Low-Strength Steel Nylon-Insert Locknut, Thin-Profile, Zinc-Plated, 10-32 Thread Size
    Pack of 100In stock
    Compatible Products for This Locknut
    12-24
    7/16"13/64"22010090633A4120000
    1/4"-20
    7/16"13/64"22010090566A0290000
    1/4"-28
    7/16"13/64"22010090566A2100000
    5/16"-18
    1/2"1/4"22010090566A0300000
    5/16"-24
    1/2"1/4"22010090566A2150000
    3/8"-16
    9/16"17/64"22010090566A0310000
    3/8"-24
    9/16"17/64"22010090566A2200000
    7/16"-14
    5/8"5/16"22010090566A03200000
    7/16"-20
    5/8"5/16"22010090566A22500000
    1/2"-13
    3/4"5/16"22010090566A03300000
    1/2"-20
    3/4"5/16"22010090566A23000000
    9/16"-12
    7/8"23/64"22010090566A23100000
    9/16"-18
    7/8"23/64"22010090566A23200000
    5/8"-11
    15/16"25/64"2205090566A03500000
    5/8"-18
    15/16"25/64"2205090566A23500000
    3/4"-10
    1 1/16"13/32"2201090566A2400000
    3/4"-16
    1 1/16"13/32"2201090566A2430000
    7/8"-9
    1 1/4"15/32"220590566A2460000
    7/8"-14
    1 1/4"15/32"220590566A2490000
    1"-8
    1 7/16"35/64"220190566A2530000
    1"-14
    1 7/16"35/64"220190566A2560000
    1 1/8"-7
    1 5/8"41/64"220190566A2590000
    1 1/4"-7
    1 13/16"3/4"220190566A2620000
    1 1/4"-12
    1 13/16"3/4"220190566A2650000
    1 3/8"-6
    2"51/64"220190566A2680000
    1 1/2"-6
    2 3/16"51/64"220190566A2710000
    M3 × 0.5 mm5.5 mm3.9 mm245ISO 105112590453A11100000
    M4 × 0.7 mm7 mm5 mm245ISO 105112590453A1120000
    M5 × 0.8 mm8 mm5 mm245ISO 105112590453A1130000
    M6 × 1 mm10 mm6 mm245ISO 105111090453A1140000
    M8 × 1.25 mm13 mm6.8 mm245ISO 10511590453A1150000
    M10 × 1.5 mm16 mm8.6 mm245ISO 10511590453A1160000
    M12 × 1.75 mm18 mm10.3 mm245ISO 10511590453A1170000
    M14 × 2 mm21 mm11.4 mm245ISO 10511590453A1180000
    M16 × 2 mm24 mm12.5 mm245ISO 10511190453A1190000
    M18 × 2.5 mm26 mm13 mm245ISO 10511190453A1210000
    M20 × 2.5 mm30 mm14.9 mm245ISO 10511190453A1220000
    M24 × 3 mm36 mm17.8 mm245ISO 10511190453A12300000
     
    Black-Zinc-Plated Steel
    6-32
    5/16"1/8"2202594627A1100000
    8-32
    11/32"11/64"2202594627A1200000
    10-24
    3/8"11/64"2202594627A1300000
    10-32
    3/8"11/64"2202594627A1400000
    12-24
    7/16"13/64"2202594627A1500000
    1/4"-20
    7/16"13/64"2202594627A1600000
    5/16"-18
    1/2"1/4"2201094627A1700000
    3/8"-16
    9/16"17/64"2201094627A1800000
     
    Black-Corrosion-Resistant-Coated Steel
    6-32
    5/16"1/8"220591581A3150000
    8-32
    11/32"11/64"220591581A3250000
    10-24
    3/8"11/64"220591581A3350000
    10-32
    3/8"11/64"220591581A3450000
    1/4"-20
    7/16"13/64"220591581A3550000
    5/16"-18
    1/2"1/4"220591581A3650000
    3/8"-16
    9/16"17/64"220591581A3750000
    1/2"-13
    3/4"5/16"220591581A3850000
     
    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.
    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"2205090101A00400000
    6-32
    5/16"1/8"22010090101A00700000
    8-32
    11/32"11/64"22010090101A0090000
    10-24
    3/8"11/64"22010090101A01100000
    10-32
    3/8"11/64"2205090101A2250000
    1/4"-20
    7/16"13/64"2205090101A2300000
    1/4"-28
    7/16"13/64"2205090101A2350000
    5/16"-18
    1/2"1/4"2205090101A2370000
    5/16"-24
    1/2"1/4"2205090101A2400000
    3/8"-16
    9/16"17/64"2202590101A2430000
    3/8"-24
    9/16"17/64"2202590101A2450000
    7/16"-14
    5/8"5/16"2201090101A2470000
    7/16"-20
    5/8"5/16"220590101A2500000
    1/2"-13
    3/4"5/16"2201090101A2520000
    1/2"-20
    3/4"5/16"220590101A2550000
    9/16"-18
    7/8"23/64"220190101A25100000
    5/8"-11
    15/16"25/64"220190101A0380000
    5/8"-18
    15/16"25/64"220190101A2600000
    3/4"-10
    1 1/16"13/32"220190101A0500000
    3/4"-16
    1 1/16"13/32"220190101A05500000
    7/8"-9
    1 1/4"15/32"220190101A0600000
    7/8"-14
    1 1/4"15/32"220190101A06500000
    1"-8
    1 7/16"35/64"220190101A07000000
    1"-14
    1 7/16"35/64"220190101A07500000
    1 1/8"-7
    1 5/8"41/64"220190101A08000000
    1 1/4"-7
    1 13/16"3/4"220190101A09000000
    1 1/4"-12
    1 13/16"3/4"220190101A09500000
    1 1/2"-6
    2 3/16"51/64"220190101A15000000
     
    Black-Oxide 18-8 Stainless Steel
    4-40
    1/4"1/8"22010090101A11500000
    6-32
    5/16"9/64"22010090101A11600000
    8-32
    11/32"3/16"22010090101A11700000
    10-24
    3/8"3/16"22010090101A11800000
    10-32
    3/8"3/16"22010090101A11900000
    1/4"-20
    7/16"13/64"2205090101A12100000
    5/16"-18
    1/2"1/4"2205090101A12200000
    3/8"-16
    9/16"17/64"2205090101A12300000
    3/8"-24
    9/16"17/64"2205090101A12400000
    1/2"-13
    3/4"5/16"220590101A1250000
    1/2"-20
    3/4"5/16"220590101A1260000
     
    316 Stainless Steel
    10-24
    3/8"11/64"2205097367A11100000
    10-32
    3/8"11/64"2205097367A11200000
    1/4"-20
    7/16"13/64"2202597367A1130000
    1/4"-28
    7/16"13/64"2205097367A13200000
    5/16"-18
    1/2"1/4"2202597367A11400000
    5/16"-24
    1/2"1/4"2205097367A13300000
    3/8"-16
    9/16"17/64"2202597367A11500000
    3/8"-24
    9/16"17/64"2202597367A13400000
    7/16"-14
    5/8"5/16"2202597367A13500000
    7/16"-20
    5/8"5/16"2202597367A13600000
    1/2"-13
    3/4"5/16"2201097367A11600000
    1/2"-20
    3/4"5/16"2201097367A13700000
    3/4"-10
    1 1/16"25/64"220197367A13100000
     
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    Other Locknuts
    Nylon-Insert LockingAbout Nylon-Insert Locking