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    153 Products

    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
    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 steel 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.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M4 × 0.7 mm75Class 10220DIN 98510094645A101000000
    M5 × 0.8 mm85Class 10220DIN 98510094645A10200000
    M6 × 1 mm106Class 10220DIN 98510094645A20500000
    M8 × 1 mm138Class 10220DIN 985, ISO 105111094645A11100000
    M8 × 1.25 mm138Class 10220DIN 9855094645A21000000
    M10 × 1 mm1710Class 10220DIN 985, ISO 105112594645A2130000
    M10 × 1.25 mm1710Class 10220DIN 985, ISO 105111094645A11200000
    M10 × 1.5 mm1710Class 10220DIN 9852594645A22000000
    M12 × 1.25 mm1912Class 10220DIN 985, ISO 105111094645A11300000
    M12 × 1.5 mm1912Class 10220DIN 985, ISO 105111094645A2290000
    M12 × 1.75 mm1912Class 10220DIN 9851094645A23000000
    M14 × 1.5 mm2214Class 10220DIN 985, ISO 10511594645A11500000
    M14 × 2 mm2214Class 10220DIN 9851094645A24000000
    M16 × 1.5 mm2416Class 10220DIN 985, ISO 10511194645A1160000
    M16 × 2 mm2416Class 10220DIN 9851094645A25000000
    M18 × 1.5 mm2718Class 10220DIN 985, ISO 10511194645A1170000
    M18 × 2.5 mm2718.5Class 10220DIN 985594645A26000000
    M20 × 1.5 mm3020Class 10220DIN 985, ISO 10511194645A1180000
    M20 × 2 mm3020Class 10220DIN 985, ISO 10511194645A11900000
    M20 × 2.5 mm3020Class 10220DIN 985594645A27000000
    M22 × 1.5 mm3222Class 10220DIN 985, ISO 10511194645A12100000
    M22 × 2.5 mm3222Class 10220DIN 985194645A3100000
    M24 × 1.5 mm3624Class 10220DIN 985, ISO 10511194645A12200000
    M24 × 2 mm3624Class 10220DIN 985, ISO 10511194645A12300000
    M24 × 3 mm3624Class 10220DIN 985194645A2800000
    M27 × 3 mm4127Class 10220DIN 985194645A32000000
    M30 × 2 mm4630Class 10220DIN 985, ISO 10511194645A12400000
    M30 × 3.5 mm4630Class 10220DIN 985194645A33000000
    M33 × 3.5 mm5033Class 10220DIN 985194645A34000000
    M36 × 3 mm5536Class 10220DIN 985, ISO 10511194645A12500000
    M36 × 4 mm5536Class 10220DIN 985194645A35000000
    M39 × 4 mm6039Class 10220DIN 985194645A36000000
    M42 × 4.5 mm6542Class 10220DIN 985194645A37000000
     
    Black-Corrosion-Resistant-Coated Steel
    M4 × 0.7 mm75Class 10220DIN 985590237A11000000
    M5 × 0.8 mm85Class 10220DIN 985590237A12000000
    M6 × 1 mm106Class 10220DIN 985590237A13000000
    M8 × 1.25 mm138Class 10220DIN 985590237A14000000
    M10 × 1.5 mm1710Class 10220DIN 985590237A15000000
    M12 × 1.75 mm1912Class 10220DIN 985190237A1600000
    M14 × 2 mm2214Class 10220DIN 985190237A1700000
     
    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.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Yellow-Chromate-Plated Steel
    M3 × 0.5 mm5.54Class 8220DIN 985, ISO 1051110090576A811000000
    M4 × 0.7 mm75Class 8220DIN 985, ISO 1051110090576A81200000
    M5 × 0.8 mm85Class 8220DIN 985, ISO 1051110090576A81300000
    M6 × 1 mm106Class 8220DIN 985, ISO 1051110090576A81400000
    M8 × 1.25 mm138Class 8220DIN 985, ISO 1051110090576A81500000
    M10 × 1.5 mm1710Class 8220DIN 985, ISO 105115090576A81600000
    M12 × 1.75 mm1912Class 8220DIN 985, ISO 105112590576A81700000
    M14 × 2 mm2214Class 8220DIN 985, ISO 105112590576A81800000
    M16 × 2 mm2416Class 8220DIN 985, ISO 105111090576A8190000
    M18 × 2.5 mm2718.5Class 8220DIN 985, ISO 10511590576A8210000
    M20 × 2.5 mm3020Class 8220DIN 985, ISO 10511590576A8220000
    M22 × 2.5 mm3222Class 8220DIN 985, ISO 10511590576A82300000
    M24 × 3 mm3624Class 8220DIN 985, ISO 10511590576A82400000
     
    Zinc-Plated Steel
    M2 × 0.4 mm42.8Class 8220DIN 9851090576A2110000
    M2.5 × 0.45 mm53.8Class 8220DIN 9855090576A1610000
    M3 × 0.5 mm5.54Class 8220DIN 985, ISO 1051110090576A1020000
    M4 × 0.7 mm75Class 8220DIN 985, ISO 1051110090576A1030000
    M5 × 0.8 mm85Class 8220DIN 985, ISO 1051110090576A1040000
    M6 × 1 mm106Class 8220DIN 985, ISO 1051110090576A1150000
    M7 × 1 mm117.5Class 8220DIN 985, ISO 105112590576A2120000
    M8 × 1 mm138Class 8220DIN 985, ISO 105112590576A1160000
    M8 × 1.25 mm138Class 8220DIN 985, ISO 1051110090576A11700000
    M10 × 1 mm1710Class 8220DIN 985, ISO 105112590576A1310000
    M10 × 1.25 mm1710Class 8220DIN 985, ISO 105112590576A13200000
    M10 × 1.5 mm1710Class 8220DIN 985, ISO 105115090576A1180000
    M12 × 1 mm1912Class 8220DIN 985, ISO 105111090576A1370000
    M12 × 1.25 mm1912Class 8220DIN 985, ISO 105112590576A14100000
    M12 × 1.5 mm1912Class 8220DIN 985, ISO 105112090576A14400000
    M12 × 1.75 mm1912Class 8220DIN 985, ISO 105115090576A11900000
    M14 × 1.5 mm2214Class 8220DIN 985, ISO 105111090576A1470000
    M14 × 2 mm2214Class 8220DIN 985, ISO 105112590576A12000000
    M16 × 1.5 mm2416Class 8220DIN 985, ISO 105111090576A15200000
    M16 × 2 mm2416Class 8220DIN 985, ISO 105112590576A12200000
    M18 × 1.5 mm2718.5Class 8220DIN 985, ISO 105111090576A10600000
    M18 × 2.5 mm2718.5Class 8220DIN 985, ISO 105111090576A12300000
    M20 × 1.5 mm3020Class 8220DIN 985, ISO 10511590576A17200000
    M20 × 2 mm3020Class 8220DIN 985, ISO 10511190576A1550000
    M20 × 2.5 mm3020Class 8220DIN 985, ISO 105111090576A12500000
    M22 × 1.5 mm3222Class 8220DIN 985, ISO 10511590576A29900000
    M22 × 2.5 mm3222Class 8220DIN 985, ISO 10511590576A16200000
    M24 × 1.5 mm3624Class 8220DIN 985, ISO 10511190576A3260000
    M24 × 2 mm3624Class 8220DIN 985, ISO 10511190576A3040000
    M24 × 3 mm3624Class 8220DIN 985, ISO 10511590576A12900000
    M27 × 1.5 mm4127Class 8220DIN 985, ISO 10511190576A3520000
    M27 × 2 mm4127Class 8220DIN 985, ISO 10511190576A3420000
    M27 × 3 mm4127Class 8220DIN 985, ISO 10511190576A1400000
    M30 × 2 mm4630Class 8220DIN 985, ISO 10511190576A36600000
    M30 × 3.5 mm4630Class 8220DIN 985, ISO 10511190576A1500000
    M33 × 2 mm5033Class 8220DIN 985, ISO 10511190576A38400000
    M33 × 3.5 mm5033Class 8220DIN 985, ISO 10511190576A16300000
    M36 × 3 mm5536Class 8220DIN 985, ISO 10511190576A45200000
    M36 × 4 mm5536Class 8220DIN 985, ISO 10511190576A16400000
    M39 × 3 mm6039Class 8220DIN 985, ISO 10511190576A52300000
    M42 × 3 mm6542Class 8220DIN 985, ISO 10511190576A53100000
    M45 × 3 mm7045Class 8220DIN 985, ISO 10511190576A54400000
    M48 × 3 mm7548Class 8220DIN 985, ISO 10511190576A72600000
    M48 × 5 mm7548Class 8220DIN 985, ISO 10511190576A16600000
     
    Black-Corrosion-Resistant-Coated Steel
    M4 × 0.7 mm75Class 8220DIN 985, ISO 10511590819A11100000
    M5 × 0.8 mm85Class 8220DIN 985, ISO 10511590819A11200000
    M6 × 1 mm106Class 8220DIN 985, ISO 10511590819A11300000
    M8 × 1.25 mm138Class 8220DIN 985, ISO 10511590819A11400000
    M10 × 1.5 mm1710Class 8220DIN 985, ISO 10511590819A11500000
    M12 × 1.75 mm1912Class 8220DIN 985, ISO 10511190819A1160000
    M14 × 2 mm2214Class 8220DIN 985, ISO 10511190819A1170000
     
    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.,
    mm
    Ht.,
    mm
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M2 × 0.4 mm42.8220DIN 9851093625A101000000
    M2.5 × 0.45 mm53.8220DIN 9852593625A1030000
    M3 × 0.5 mm5.54220DIN 98510093625A1000000
    M4 × 0.7 mm75220DIN 98510093625A1500000
    M5 × 0.8 mm85220DIN 98510093625A2000000
    M6 × 1 mm106220DIN 98510093625A25000000
    M8 × 1 mm138220DIN 985593625A11000000
    M8 × 1.25 mm138220DIN 9855093625A30000000
    M10 × 1 mm1710220DIN 985593625A12000000
    M10 × 1.5 mm1710220DIN 9851093625A3500000
    M12 × 1.5 mm1912220DIN 985193625A1300000
    M12 × 1.75 mm1912220DIN 9851093625A4000000
    M14 × 1.5 mm2214220DIN 985193625A1400000
    M14 × 2 mm2214220DIN 985593625A4500000
    M16 × 1.5 mm2416220DIN 985193625A16000000
    M16 × 2 mm2416220DIN 985593625A5000000
    M18 × 1.5 mm2718220DIN 985193625A17000000
    M18 × 2.5 mm2718.5220DIN 985193625A5100000
    M20 × 1.5 mm3020220DIN 985193625A18000000
    M20 × 2.5 mm3020220DIN 985193625A5500000
    M22 × 2.5 mm3222220DIN 985193625A7600000
    M24 × 3 mm3624220DIN 985193625A6000000
    M27 × 3 mm4127220DIN 985193625A70000000
    M30 × 3.5 mm4630220DIN 985193625A75000000
     
    Black-Oxide 18-8 Stainless Steel
    M2 × 0.4 mm43240DIN 985593625A2210000
    M2.5 × 0.45 mm53.8240DIN 9851093625A2220000
    M3 × 0.5 mm5.54240DIN 9851093625A2230000
    M4 × 0.7 mm75240DIN 9851093625A2240000
    M5 × 0.8 mm85240DIN 9851093625A2250000
    M6 × 1 mm106240DIN 9851093625A2260000
    M8 × 1.25 mm138240DIN 9851093625A2270000
    M10 × 1.5 mm1710240DIN 9851093625A22800000
    M12 × 1.75 mm1912240DIN 985593625A2290000
     
    316 Stainless Steel
    M2.5 × 0.45 mm53.8220DIN 9855094205A10100000
    M3 × 0.5 mm5.54220DIN 9855094205A2200000
    M4 × 0.7 mm75220DIN 9855094205A2300000
    M5 × 0.8 mm85220DIN 9855094205A2400000
    M6 × 1 mm106220DIN 9855094205A25000000
    M8 × 1.25 mm138220DIN 9852594205A2600000
    M10 × 1.5 mm1710220DIN 9851094205A27000000
    M12 × 1.75 mm1912220DIN 9851094205A28000000
    M14 × 2 mm2214220DIN 985194205A2900000
    M16 × 2 mm2416220DIN 985594205A31000000
    M18 × 2.5 mm2718.5220DIN 985194205A31500000
    M20 × 2.5 mm3020220DIN 985194205A3200000
    M22 × 2.5 mm3222220DIN 985194205A1110000
    M24 × 3 mm3624220DIN 985194205A33000000
    M27 × 3 mm4127220DIN 985194205A35000000
    M30 × 3.5 mm4630220DIN 985194205A38000000
     
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