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    142 Products

    Serrated Flange Nuts

    Serrations bite into material for mild vibration resistance while the flange eliminates the need for a separate washer. These nuts are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. You can use them again and again without sacrificing strength. However, the serrations may mar the surface of your material. Also known as collar nuts.
    Medium-Strength Steel
    Image of Product. Bottom orientation. Flange Nuts. Serrated Flange Nuts.
    Rated Grade 5, Grade F, or Class 8, these 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.
    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.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating that creates a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Flange,
    mm
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M3 × 0.5 mm5.5480.7Class 8DIN 6923, ISO 416110000000000000000
    M4 × 0.7 mm74.6100.4Class 8DIN 69231000000000000000
    M5 × 0.8 mm8511.81Class 8DIN 69231000000000000000
    M6 × 1 mm10614.21.1Class 8DIN 6923, ISO 41611000000000000000
    M8 × 1 mm13817.91.2Class 8DIN 692310000000000000000
    M8 × 1.25 mm13817.91.2Class 8DIN 6923, ISO 416110000000000000000
    M10 × 1.25 mm151021.81.5Class 8DIN 69235000000000000000
    M10 × 1.5 mm151021.81.5Class 8DIN 69235000000000000000
    M12 × 1.75 mm1812261.8Class 8DIN 69232500000000000000
    M14 × 2 mm211429.92.1Class 8DIN 69232500000000000000
    M16 × 2 mm241634.52.4Class 8DIN 6923, ISO 41611000000000000000
    M20 × 2.5 mm302042.83Class 8DIN 6923, ISO 416110000000000000
     
    Zinc-Yellow-Chromate-Plated Steel
    M4 × 0.7 mm74.210.50.9Class 8DIN 6923, ISO 41615000000000000000
    M5 × 0.8 mm8511.81Class 8DIN 6923, ISO 41615000000000000000
    M6 × 1 mm10614.21.1Class 8DIN 6923, ISO 416110000000000000000
    M8 × 1.25 mm13817.91.2Class 8DIN 6923, ISO 41615000000000000000
    M10 × 1.25 mm151021.81.5Class 8DIN 69235000000000000000
    M10 × 1.5 mm151021.81.5Class 8DIN 6923, ISO 41612500000000000000
    M12 × 1.75 mm1812261.8Class 8DIN 6923, ISO 41611000000000000000
    M14 × 2 mm211429.92.1Class 8DIN 69232500000000000000
    M16 × 2 mm241634.52.4Class 8DIN 6923, ISO 416110000000000000
     
    Black-Oxide Steel
    M4 × 0.7 mm74.6100.4Class 8DIN 69231000000000000000
    M5 × 0.8 mm8511.81Class 8DIN 69231000000000000000
    M6 × 1 mm10614.21.1Class 8DIN 69231000000000000000
    M8 × 1 mm13817.91.2Class 8DIN 692310000000000000000
    M8 × 1.25 mm13817.91.2Class 8DIN 692310000000000000000
    M10 × 1.25 mm151021.81.5Class 8DIN 69235000000000000000
    M10 × 1.5 mm151021.81.5Class 8DIN 69235000000000000000
    M12 × 1.75 mm1812261.8Class 8DIN 69232500000000000000
     
    Steel
    M4 × 0.7 mm74.6100.4Class 8DIN 69231000000000000000
    M8 × 1 mm13817.91.2Class 8DIN 692310000000000000000
    M10 × 1.25 mm151021.81.5Class 8DIN 6923500000000000000
    M12 × 1.75 mm1812261.8Class 8DIN 6923, ISO 41612500000000000000
    M14 × 2 mm211429.92.1Class 8DIN 69232500000000000000
    M16 × 2 mm241634.52.4Class 8DIN 6923100000000000000
     
    High-Strength Steel
    Image of Product. Bottom orientation. Flange Nuts. Serrated Flange Nuts.
    Rated Grade 8, Grade G, or Class 10, these are about 25% stronger than medium-strength steel nuts. They are commonly used to fasten components in valves, pumps, and motors. 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.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Flange,
    mm
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M5 × 0.8 mm8511.81Class 10DIN 69232500000000000000
    M6 × 1 mm10614.21.1Class 10DIN 69235000000000000000
    M8 × 1.25 mm13817.91.2Class 10DIN 69235000000000000000
    M10 × 1.5 mm151021.81.5Class 10DIN 69232500000000000000
    M12 × 1.75 mm1812261.8Class 10DIN 6923100000000000000
    M16 × 2 mm241634.52.4Class 10DIN 6923500000000000000
    M20 × 2.5 mm302042.83Class 10DIN 692310000000000000
     
    Steel
    M5 × 0.8 mm8511.81Class 10DIN 6923250000000000000
    M6 × 1 mm10614.21.1Class 10DIN 69235000000000000000
    M8 × 1.25 mm13817.91.2Class 10DIN 69235000000000000000
    M10 × 1.5 mm151021.81.5Class 10DIN 69232500000000000000
    M12 × 1.75 mm1812261.8Class 10DIN 69231000000000000000
    M16 × 2 mm241634.52.4Class 10DIN 6923500000000000000
    M20 × 2.5 mm302042.83Class 10DIN 692310000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Bottom orientation. Flange Nuts. Serrated Flange Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Highly Corrosion-Resistant 316 Stainless Steel—Our most corrosion-resistant flange nuts, these hold up in just about any environment, including harsh weather, salt water, and most chemicals.
    Flange,
    mm
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Dia.
    Thk.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M3 × 0.5 mm5.5480.7DIN 692310000000000000000
    M4 × 0.7 mm74.65101DIN 692310000000000000000
    M5 × 0.8 mm85111DIN 692310000000000000000
    M6 × 1 mm10614.21.18DIN 6923500000000000000
    M8 × 1.25 mm13817.91.3DIN 6923250000000000000
    M10 × 1.5 mm151021.81.8DIN 6923250000000000000
    M12 × 1.75 mm1812262.19DIN 6923100000000000000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    M3 × 0.5 mm5.5480.7DIN 69232500000000000000
    M4 × 0.7 mm74.65101DIN 69232500000000000000
    M5 × 0.8 mm8511.81DIN 69232500000000000000
    M6 × 1 mm10614.21.18DIN 6923250000000000000
    M8 × 1.25 mm13817.91.3DIN 6923100000000000000
    M10 × 1.5 mm151021.81.8DIN 6923100000000000000
    M12 × 1.75 mm1812262.19DIN 692350000000000000
     

    Flange Nuts

    No need for a separate washer—these nuts have a plain flange that distributes pressure evenly for a wide variety of fastening applications. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. Also known as collar nuts.
    Medium-Strength Steel
    Image of Product. Front orientation. Flange Nuts. Flange Nuts.
    Rated Grade 5, Grade F, or Class 8, these 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.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Flange,
    mm
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M3 × 0.5 mm5.5480.8Class 8DIN 69235000000000000000
    M4 × 0.7 mm74.65101.65Class 8DIN 6923, ISO 41611000000000000000
    M5 × 0.8 mm8511.82.8Class 8DIN 6923, ISO 41611000000000000000
    M6 × 1 mm10614.22.9Class 8DIN 6923, ISO 41611000000000000000
    M8 × 1 mm13817.93.5Class 8DIN 6923, ISO 4161500000000000000
    M8 × 1.25 mm13817.93.5Class 8DIN 6923, ISO 416110000000000000000
    M10 × 1.25 mm151021.84.5Class 8DIN 6923, ISO 41615000000000000000
    M10 × 1.5 mm151021.84.5Class 8DIN 6923, ISO 4161500000000000000
    M12 × 1.25 mm1812265.3Class 8DIN 6923, ISO 4161250000000000000
    M12 × 1.5 mm1812265.3Class 8DIN 6923, ISO 4161100000000000000
    M12 × 1.75 mm1812265.3Class 8DIN 6923, ISO 41612500000000000000
    M14 × 2 mm211429.96.2Class 8DIN 6923, ISO 4161100000000000000
    M16 × 1.5 mm241634.57Class 8DIN 6923, ISO 416110000000000000
    M16 × 2 mm241634.57Class 8DIN 6923, ISO 41611000000000000000
    M20 × 2.5 mm302042.89Class 8DIN 6923, ISO 4161500000000000000
     
    Steel
    M6 × 1 mm10614.21.1Class 8DIN 69231000000000000000
    M8 × 1.25 mm13817.91.2Class 8DIN 6923500000000000000
    M10 × 1.25 mm151021.81.5Class 8DIN 6923250000000000000
    M10 × 1.5 mm151021.81.5Class 8DIN 6923250000000000000
    M12 × 1.25 mm1812261.8Class 8DIN 6923100000000000000
    M12 × 1.5 mm1812261.8Class 8DIN 6923100000000000000
    M12 × 1.75 mm1812261.8Class 8DIN 6923250000000000000
    M16 × 1.5 mm241634.52.4Class 8DIN 692350000000000000
    M16 × 2 mm241634.52.4Class 8DIN 6923100000000000000
     
    High-Strength Steel
    Image of Product. Front orientation. Flange Nuts. Flange Nuts.
    Rated Grade 8, Grade G, or Class 10, these are about 25% stronger than medium-strength steel nuts. They are commonly used to fasten components in valves, pumps, and motors. 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.
    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.
    Black Phosphate-Coated Steel—The dark coating creates both a finished appearance and a barrier against rust that withstands occasional exposure to moisture.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Flange,
    mm
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M5 × 0.8 mm8511.81Class 10DIN 6923, ISO 416125000000000000000
    M6 × 1 mm10614.21.1Class 10DIN 6923, ISO 41611000000000000000
    M8 × 1.25 mm13817.91.2Class 10DIN 6923, ISO 416110000000000000000
    M10 × 1.25 mm151021.81.5Class 10DIN 6923, ISO 4161100000000000000
    M10 × 1.5 mm151021.81.5Class 10DIN 6923, ISO 41615000000000000000
    M12 × 1.25 mm1812261.8Class 10DIN 6923, ISO 416150000000000000
    M12 × 1.5 mm1812261.8Class 10DIN 6923, ISO 416150000000000000
    M12 × 1.75 mm1812261.8Class 10DIN 6923, ISO 41612500000000000000
    M14 × 1.5 mm211429.92.1Class 10DIN 6923, ISO 41611000000000000000
    M16 × 1.5 mm241634.52.4Class 10DIN 6923, ISO 416110000000000000
    M16 × 2 mm241634.52.4Class 10DIN 6923, ISO 41611000000000000000
    M20 × 2.5 mm302042.83Class 10DIN 6923, ISO 416110000000000000
    M24 × 3 mm3624513.6Class 10DIN 6923, ISO 4161100000000000000
     
    Zinc-Yellow-Chromate-Plated Steel
    M6 × 1 mm10614.21.1Class 10DIN 6923, ISO 4161500000000000000
    M8 × 1.25 mm13817.51.2Class 10DIN 6923, ISO 4161250000000000000
    M10 × 1.5 mm151021.81.5Class 10DIN 6923, ISO 4161100000000000000
    M12 × 1.25 mm1812261.8Class 10DIN 6923, ISO 4161500000000000000
    M12 × 1.5 mm1812261.8Class 10DIN 6923, ISO 4161500000000000000
    M12 × 1.75 mm1812261.8Class 10DIN 6923, ISO 4161100000000000000
    M14 × 2 mm211429.92.1Class 10DIN 6923, ISO 4161500000000000000
    M16 × 1.5 mm241634.52.4Class 10DIN 6923, ISO 416110000000000000
    M16 × 2 mm241634.52.4Class 10DIN 6923, ISO 4161500000000000000
    M20 × 2.5 mm302042.83Class 10DIN 6923, ISO 416110000000000000
     
    Black Phosphate-Coated Steel
    M5 × 0.8 mm8511.81Class 10DIN 6923, ISO 41611000000000000000
    M6 × 1 mm10614.21.1Class 10DIN 6923, ISO 416110000000000000000
    M8 × 1.25 mm13817.91.2Class 10DIN 6923, ISO 416110000000000000000
    M10 × 1.25 mm151021.81.5Class 10DIN 6923, ISO 41611000000000000000
    M10 × 1.5 mm151021.81.5Class 10DIN 6923, ISO 41615000000000000000
    M12 × 1.25 mm1812261.8Class 10DIN 6923, ISO 4161500000000000000
    M12 × 1.5 mm1812261.8Class 10DIN 6923, ISO 4161500000000000000
    M12 × 1.75 mm1812261.8Class 10DIN 6923, ISO 41612500000000000000
    M16 × 1.5 mm241634.52.4Class 10DIN 6923, ISO 416110000000000000
    M16 × 2 mm241634.52.4Class 10DIN 6923, ISO 41611000000000000000
     
    Steel
    M5 × 0.8 mm8511.81Class 10DIN 6923, ISO 416110000000000000000
    M6 × 1 mm10614.21.1Class 10DIN 6923, ISO 416110000000000000000
    M8 × 1.25 mm13817.91.2Class 10DIN 6923, ISO 4161500000000000000
    M10 × 1.5 mm151021.81.5Class 10DIN 6923, ISO 41615000000000000000
    M12 × 1.75 mm1812261.8Class 10DIN 6923, ISO 41612500000000000000
    M14 × 2 mm211429.92.1Class 10DIN 6923, ISO 4161100000000000000
    M16 × 2 mm241634.52.4Class 10DIN 6923, ISO 41611000000000000000
    M20 × 2.5 mm302042.83Class 10DIN 6923, ISO 4161500000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Flange Nuts. Flange Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Highly Corrosion-Resistant 316 Stainless Steel—Our most corrosion-resistant flange nuts, these hold up in just about any environment, including harsh weather, salt water, and most chemicals.
    Flange,
    mm
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Dia.
    Thk.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M3 × 0.5 mm5.5481DIN 6923, ISO 416110000000000000000
    M4 × 0.7 mm74100.9DIN 6923, ISO 41615000000000000000
    M5 × 0.8 mm8511.81DIN 6923, ISO 4161500000000000000
    M6 × 1 mm10614.21.19DIN 6923, ISO 4161500000000000000
    M8 × 1.25 mm13817.91.31DIN 6923, ISO 4161250000000000000
    M10 × 1.5 mm151021.81.81DIN 6923, ISO 4161100000000000000
    M12 × 1.75 mm1812262.2DIN 6923, ISO 41611000000000000000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    M3 × 0.5 mm5.5480.7DIN 69231000000000000000
    M4 × 0.7 mm74100.9DIN 692310000000000000000
    M5 × 0.8 mm8511.81DIN 692310000000000000000
    M6 × 1 mm10614.21.19DIN 69235000000000000000
    M8 × 1.25 mm13817.91.31DIN 6923100000000000000
    M10 × 1.5 mm151021.81.81DIN 6923100000000000000
    M12 × 1.75 mm1812262.2DIN 692350000000000000
     
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