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    153 Products

    Nylon-Insert Locknuts
    3D CAD models available

    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
    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknuts.
    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.
    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.
    Fastener Strength
    Grade/Class
    Insert
    Max.
    Temp.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M4 × 0.7 mm7 mm5 mmISO Class 10
    220° FDIN 985100000000000000000
    M5 × 0.8 mm8 mm5 mmISO Class 10
    220° FDIN 98510000000000000000
    M6 × 1 mm10 mm6 mmISO Class 10
    220° FDIN 98510000000000000000
    M8 × 1 mm13 mm8 mmISO Class 10
    220° FDIN 985, ISO 105111000000000000000
    M8 × 1.25 mm13 mm8 mmISO Class 10
    220° FDIN 9855000000000000000
    M10 × 1 mm17 mm10 mmISO Class 10
    220° FDIN 985, ISO 105112500000000000000
    M10 × 1.25 mm17 mm10 mmISO Class 10
    220° FDIN 985, ISO 105111000000000000000
    M10 × 1.5 mm17 mm10 mmISO Class 10
    220° FDIN 9852500000000000000
    M12 × 1.25 mm19 mm12 mmISO Class 10
    220° FDIN 985, ISO 105111000000000000000
    M12 × 1.5 mm19 mm12 mmISO Class 10
    220° FDIN 985, ISO 105111000000000000000
    M12 × 1.75 mm19 mm12 mmISO Class 10
    220° FDIN 9851000000000000000
    M14 × 1.5 mm22 mm14 mmISO Class 10
    220° FDIN 985, ISO 10511500000000000000
    M14 × 2 mm22 mm14 mmISO Class 10
    220° FDIN 9851000000000000000
    M16 × 1.5 mm24 mm16 mmISO Class 10
    220° FDIN 985, ISO 1051110000000000000
    M16 × 2 mm24 mm16 mmISO Class 10
    220° FDIN 9851000000000000000
    M18 × 1.5 mm27 mm18 mmISO Class 10
    220° FDIN 985, ISO 1051110000000000000
    M18 × 2.5 mm27 mm18.5 mmISO Class 10
    220° FDIN 985500000000000000
    M20 × 1.5 mm30 mm20 mmISO Class 10
    220° FDIN 985, ISO 1051110000000000000
    M20 × 2 mm30 mm20 mmISO Class 10
    220° FDIN 985, ISO 10511100000000000000
    M20 × 2.5 mm30 mm20 mmISO Class 10
    220° FDIN 985500000000000000
    M22 × 1.5 mm32 mm22 mmISO Class 10
    220° FDIN 985, ISO 10511100000000000000
    M22 × 2.5 mm32 mm22 mmISO Class 10
    220° FDIN 98510000000000000
    M24 × 1.5 mm36 mm24 mmISO Class 10
    220° FDIN 985, ISO 10511100000000000000
    M24 × 2 mm36 mm24 mmISO Class 10
    220° FDIN 985, ISO 10511100000000000000
    M24 × 3 mm36 mm24 mmISO Class 10
    220° FDIN 98510000000000000
    M27 × 3 mm41 mm27 mmISO Class 10
    220° FDIN 985100000000000000
    M30 × 2 mm46 mm30 mmISO Class 10
    220° FDIN 985, ISO 10511100000000000000
    M30 × 3.5 mm46 mm30 mmISO Class 10
    220° FDIN 985100000000000000
    M33 × 3.5 mm50 mm33 mmISO Class 10
    220° FDIN 985100000000000000
    M36 × 3 mm55 mm36 mmISO Class 10
    220° FDIN 985, ISO 10511100000000000000
    M36 × 4 mm55 mm36 mmISO Class 10
    220° FDIN 985100000000000000
    M39 × 4 mm60 mm39 mmISO Class 10
    220° FDIN 985100000000000000
    M42 × 4.5 mm65 mm42 mmISO Class 10
    220° FDIN 985100000000000000
     
    Black Corrosion-Resistant-Coated Steel
    M4 × 0.7 mm7 mm5 mmISO Class 10
    220° FDIN 985500000000000000
    M5 × 0.8 mm8 mm5 mmISO Class 10
    220° FDIN 985500000000000000
    M6 × 1 mm10 mm6 mmISO Class 10
    220° FDIN 985500000000000000
    M8 × 1.25 mm13 mm8 mmISO Class 10
    220° FDIN 985500000000000000
    M10 × 1.5 mm17 mm10 mmISO Class 10
    220° FDIN 985500000000000000
    M12 × 1.75 mm19 mm12 mmISO Class 10
    220° FDIN 98510000000000000
    M14 × 2 mm22 mm14 mmISO Class 10
    220° FDIN 98510000000000000
     
    Medium-Strength Steel
    Image of Product. Front orientation. Locknuts. 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 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 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.
    Fastener Strength
    Grade/Class
    Insert
    Max.
    Temp.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc Yellow-Chromate-Plated Steel
    M3 × 0.5 mm5.5 mm4 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000000
    M4 × 0.7 mm7 mm5 mmISO Class 8
    220° FDIN 985, ISO 1051110000000000000000
    M5 × 0.8 mm8 mm5 mmISO Class 8
    220° FDIN 985, ISO 1051110000000000000000
    M6 × 1 mm10 mm6 mmISO Class 8
    220° FDIN 985, ISO 1051110000000000000000
    M8 × 1.25 mm13 mm8 mmISO Class 8
    220° FDIN 985, ISO 1051110000000000000000
    M10 × 1.5 mm17 mm10 mmISO Class 8
    220° FDIN 985, ISO 105115000000000000000
    M12 × 1.75 mm19 mm12 mmISO Class 8
    220° FDIN 985, ISO 105112500000000000000
    M14 × 2 mm22 mm14 mmISO Class 8
    220° FDIN 985, ISO 105112500000000000000
    M16 × 2 mm24 mm16 mmISO Class 8
    220° FDIN 985, ISO 105111000000000000000
    M18 × 2.5 mm27 mm18.5 mmISO Class 8
    220° FDIN 985, ISO 10511500000000000000
    M20 × 2.5 mm30 mm20 mmISO Class 8
    220° FDIN 985, ISO 10511500000000000000
    M22 × 2.5 mm32 mm22 mmISO Class 8
    220° FDIN 985, ISO 10511500000000000000
    M24 × 3 mm36 mm24 mmISO Class 8
    220° FDIN 985, ISO 10511500000000000000
     
    Zinc-Plated Steel
    M2 × 0.4 mm4 mm2.8 mmISO Class 8
    220° FDIN 9851000000000000000
    M2.5 × 0.45 mm5 mm3.8 mmISO Class 8
    220° FDIN 9855000000000000000
    M3 × 0.5 mm5.5 mm4 mmISO Class 8
    220° FDIN 985, ISO 105111000000000000000
    M4 × 0.7 mm7 mm5 mmISO Class 8
    220° FDIN 985, ISO 105111000000000000000
    M5 × 0.8 mm8 mm5 mmISO Class 8
    220° FDIN 985, ISO 105111000000000000000
    M6 × 1 mm10 mm6 mmISO Class 8
    220° FDIN 985, ISO 105111000000000000000
    M7 × 1 mm11 mm7.5 mmISO Class 8
    220° FDIN 985, ISO 105112500000000000000
    M8 × 1 mm13 mm8 mmISO Class 8
    220° FDIN 985, ISO 10511250000000000000
    M8 × 1.25 mm13 mm8 mmISO Class 8
    220° FDIN 985, ISO 1051110000000000000000
    M10 × 1 mm17 mm10 mmISO Class 8
    220° FDIN 985, ISO 105112500000000000000
    M10 × 1.25 mm17 mm10 mmISO Class 8
    220° FDIN 985, ISO 105112500000000000000
    M10 × 1.5 mm17 mm10 mmISO Class 8
    220° FDIN 985, ISO 105115000000000000000
    M12 × 1 mm19 mm12 mmISO Class 8
    220° FDIN 985, ISO 105111000000000000000
    M12 × 1.25 mm19 mm12 mmISO Class 8
    220° FDIN 985, ISO 105112500000000000000
    M12 × 1.5 mm19 mm12 mmISO Class 8
    220° FDIN 985, ISO 105112000000000000000
    M12 × 1.75 mm19 mm12 mmISO Class 8
    220° FDIN 985, ISO 105115000000000000000
    M14 × 1.5 mm22 mm14 mmISO Class 8
    220° FDIN 985, ISO 105111000000000000000
    M14 × 2 mm22 mm14 mmISO Class 8
    220° FDIN 985, ISO 105112500000000000000
    M16 × 1.5 mm24 mm16 mmISO Class 8
    220° FDIN 985, ISO 105111000000000000000
    M16 × 2 mm24 mm16 mmISO Class 8
    220° FDIN 985, ISO 105112500000000000000
    M18 × 1.5 mm27 mm18.5 mmISO Class 8
    220° FDIN 985, ISO 105111000000000000000
    M18 × 2.5 mm27 mm18.5 mmISO Class 8
    220° FDIN 985, ISO 105111000000000000000
    M20 × 1.5 mm30 mm20 mmISO Class 8
    220° FDIN 985, ISO 10511500000000000000
    M20 × 2 mm30 mm20 mmISO Class 8
    220° FDIN 985, ISO 1051110000000000000
    M20 × 2.5 mm30 mm20 mmISO Class 8
    220° FDIN 985, ISO 105111000000000000000
    M22 × 1.5 mm32 mm22 mmISO Class 8
    220° FDIN 985, ISO 10511500000000000000
    M22 × 2.5 mm32 mm22 mmISO Class 8
    220° FDIN 985, ISO 10511500000000000000
    M24 × 1.5 mm36 mm24 mmISO Class 8
    220° FDIN 985, ISO 1051110000000000000
    M24 × 2 mm36 mm24 mmISO Class 8
    220° FDIN 985, ISO 1051110000000000000
    M24 × 3 mm36 mm24 mmISO Class 8
    220° FDIN 985, ISO 10511500000000000000
    M27 × 1.5 mm41 mm27 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000
    M27 × 2 mm41 mm27 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000
    M27 × 3 mm41 mm27 mmISO Class 8
    220° FDIN 985, ISO 1051110000000000000
    M30 × 2 mm46 mm30 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000
    M30 × 3.5 mm46 mm30 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000
    M33 × 2 mm50 mm33 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000
    M33 × 3.5 mm50 mm33 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000
    M36 × 3 mm55 mm36 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000
    M36 × 4 mm55 mm36 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000
    M39 × 3 mm60 mm39 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000
    M42 × 3 mm65 mm42 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000
    M45 × 3 mm70 mm45 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000
    M48 × 3 mm75 mm48 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000
    M48 × 5 mm75 mm48 mmISO Class 8
    220° FDIN 985, ISO 10511100000000000000
     
    Black Corrosion-Resistant-Coated Steel
    M4 × 0.7 mm7 mm5 mmISO Class 8
    220° FDIN 985, ISO 10511500000000000000
    M5 × 0.8 mm8 mm5 mmISO Class 8
    220° FDIN 985, ISO 10511500000000000000
    M6 × 1 mm10 mm6 mmISO Class 8
    220° FDIN 985, ISO 10511500000000000000
    M8 × 1.25 mm13 mm8 mmISO Class 8
    220° FDIN 985, ISO 10511500000000000000
    M10 × 1.5 mm17 mm10 mmISO Class 8
    220° FDIN 985, ISO 10511500000000000000
    M12 × 1.75 mm19 mm12 mmISO Class 8
    220° FDIN 985, ISO 1051110000000000000
    M14 × 2 mm22 mm14 mmISO Class 8
    220° FDIN 985, ISO 1051110000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Locknuts. 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.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M2 × 0.4 mm4 mm2.8 mm220° FDIN 9851000000000000000
    M2.5 × 0.45 mm5 mm3.8 mm220° FDIN 985250000000000000
    M3 × 0.5 mm5.5 mm4 mm220° FDIN 9851000000000000000
    M4 × 0.7 mm7 mm5 mm220° FDIN 9851000000000000000
    M5 × 0.8 mm8 mm5 mm220° FDIN 9851000000000000000
    M6 × 1 mm10 mm6 mm220° FDIN 9851000000000000000
    M8 × 1 mm13 mm8 mm220° FDIN 985500000000000000
    M8 × 1.25 mm13 mm8 mm220° FDIN 9855000000000000000
    M10 × 1 mm17 mm10 mm220° FDIN 985500000000000000
    M10 × 1.5 mm17 mm10 mm220° FDIN 985100000000000000
    M12 × 1.5 mm19 mm12 mm220° FDIN 98510000000000000
    M12 × 1.75 mm19 mm12 mm220° FDIN 985100000000000000
    M14 × 1.5 mm22 mm14 mm220° FDIN 98510000000000000
    M14 × 2 mm22 mm14 mm220° FDIN 985500000000000000
    M16 × 1.5 mm24 mm16 mm220° FDIN 98510000000000000
    M16 × 2 mm24 mm16 mm220° FDIN 98550000000000000
    M18 × 1.5 mm27 mm18 mm220° FDIN 985100000000000000
    M18 × 2.5 mm27 mm18.5 mm220° FDIN 98510000000000000
    M20 × 1.5 mm30 mm20 mm220° FDIN 985100000000000000
    M20 × 2.5 mm30 mm20 mm220° FDIN 98510000000000000
    M22 × 2.5 mm32 mm22 mm220° FDIN 98510000000000000
    M24 × 3 mm36 mm24 mm220° FDIN 985100000000000000
    M27 × 3 mm41 mm27 mm220° FDIN 985100000000000000
    M30 × 3.5 mm46 mm30 mm220° FDIN 985100000000000000
     
    Black-Oxide 18-8 Stainless Steel
    M2 × 0.4 mm4 mm3 mm240° FDIN 98550000000000000
    M2.5 × 0.45 mm5 mm3.8 mm240° FDIN 985100000000000000
    M3 × 0.5 mm5.5 mm4 mm240° FDIN 985100000000000000
    M4 × 0.7 mm7 mm5 mm240° FDIN 985100000000000000
    M5 × 0.8 mm8 mm5 mm240° FDIN 985100000000000000
    M6 × 1 mm10 mm6 mm240° FDIN 985100000000000000
    M8 × 1.25 mm13 mm8 mm240° FDIN 985100000000000000
    M10 × 1.5 mm17 mm10 mm240° FDIN 9851000000000000000
    M12 × 1.75 mm19 mm12 mm240° FDIN 98550000000000000
     
    316 Stainless Steel
    M2.5 × 0.45 mm5 mm3.8 mm220° FDIN 985500000000000000
    M3 × 0.5 mm5.5 mm4 mm220° FDIN 985500000000000000
    M4 × 0.7 mm7 mm5 mm220° FDIN 985500000000000000
    M5 × 0.8 mm8 mm5 mm220° FDIN 985500000000000000
    M6 × 1 mm10 mm6 mm220° FDIN 9855000000000000000
    M8 × 1.25 mm13 mm8 mm220° FDIN 985250000000000000
    M10 × 1.5 mm17 mm10 mm220° FDIN 9851000000000000000
    M12 × 1.75 mm19 mm12 mm220° FDIN 9851000000000000000
    M14 × 2 mm22 mm14 mm220° FDIN 98510000000000000
    M16 × 2 mm24 mm16 mm220° FDIN 985500000000000000
    M18 × 2.5 mm27 mm18.5 mm220° FDIN 985100000000000000
    M20 × 2.5 mm30 mm20 mm220° FDIN 98510000000000000
    M22 × 2.5 mm32 mm22 mm220° FDIN 98510000000000000
    M24 × 3 mm36 mm24 mm220° FDIN 985100000000000000
    M27 × 3 mm41 mm27 mm220° FDIN 985100000000000000
    M30 × 3.5 mm46 mm30 mm220° FDIN 985100000000000000
     
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