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    90 Products

    Coupling Nuts

    Also known as extension nuts, these are commonly used to connect lengths of threaded rod and join threaded parts.
    Low-Strength Steel
    Image of Product. Front orientation. Coupling Nuts. Coupling Nuts.
    Rated Grade 2 or lower, these are about half as strong as medium-strength steel coupling nuts. Use them with threaded rods that have a comparable 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-Oxide Steel—A dark, matte coating creates a finished look. Nuts offer minimal corrosion resistance, so they're best for dry environments.
    Each
    Thread Size
    Lg.,
    mm
    Wd.,
    mm
    Threading
    Specs.
    Met
    1-9
    10-Up
    Zinc-Plated Steel
    M4 × 0.7 mm127Fully ThreadedDIN 633493355A3100000000000
    M5 × 0.8 mm158Fully ThreadedDIN 633493355A32000000000
    M6 × 1 mm1810Fully ThreadedDIN 633493355A33000000000
    M8 × 1.25 mm2413Fully ThreadedDIN 633493355A34000000000
    M10 × 1.5 mm3017Fully ThreadedDIN 633493355A35000000000
    M12 × 1.75 mm3619Fully ThreadedDIN 633493355A36000000000
    M14 × 2 mm4222Fully ThreadedDIN 633493355A37000000000
    M16 × 2 mm4824Fully ThreadedDIN 633493355A38000000000
    M18 × 2.5 mm5427Fully ThreadedDIN 633493355A5500000000000
    M20 × 2.5 mm6030Fully ThreadedDIN 633493355A39000000000
    M22 × 2.5 mm6632Fully ThreadedDIN 633493355A5600000000000
    M24 × 3 mm7236Fully ThreadedDIN 633493355A4100000000000
    M27 × 3 mm8141Fully ThreadedDIN 633493355A5700000000000
    M30 × 3.5 mm9046Fully ThreadedDIN 633493355A58000000000000
    M36 × 4 mm10855Fully ThreadedDIN 633493355A59000000000000
     
    Black-Oxide Steel
    M18 × 2.5 mm5427Fully ThreadedDIN 633493020A1070000000000
    M22 × 2.5 mm6632Fully ThreadedDIN 633493020A1080000000000
    M27 × 3 mm8141Fully ThreadedDIN 633493020A1090000000000
    M30 × 3.5 mm9046Fully ThreadedDIN 633493020A1110000000000
    M36 × 4 mm10855Fully ThreadedDIN 633493020A11200000000000
     
    Medium-Strength Steel
    Image of Product. Front orientation. Coupling Nuts. Coupling Nuts.
    These Grade 5 or Class 8 nuts are about twice as strong as low-strength steel coupling nuts. Use them with threaded rods that have a comparable 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-Oxide Steel—A dark, matte coating creates a finished look. Nuts offer minimal corrosion resistance, so they're best for dry environments.
    Each
    Thread Size
    Lg.,
    mm
    Wd.,
    mm
    Fastener Strength
    Grade/Class
    Threading
    Specs. Met
    1-9
    10-Up
    Zinc-Plated Steel
    M5 × 0.8 mm158ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490009A231000000000000
    M6 × 1 mm1810ISO Class 8
    Fully ThreadedDIN 633490009A22100000000
    M8 × 1.25 mm2413ISO Class 8
    Fully ThreadedDIN 633490009A22200000000
    M10 × 1.5 mm3017ISO Class 8
    Fully ThreadedDIN 633490009A22300000000
    M12 × 1.75 mm3619ISO Class 8
    Fully ThreadedDIN 633490009A22400000000
    M14 × 2 mm4222ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490009A2320000000000
    M16 × 2 mm4824ISO Class 8
    Fully ThreadedDIN 633490009A22500000000
    M18 × 2.5 mm5427ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490009A2330000000000
    M20 × 2.5 mm6030ISO Class 8
    Fully ThreadedDIN 633490009A226000000000
    M22 × 2.5 mm6632ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490009A2340000000000
    M24 × 3 mm7236ISO Class 8
    Fully ThreadedDIN 633490009A2270000000000
    M30 × 3.5 mm9046ISO Class 8
    Fully ThreadedDIN 633490009A2280000000000
     
    Black-Oxide Steel
    M5 × 0.8 mm158ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490082A112000000000
    M6 × 1 mm1810ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490082A1130000000000
    M8 × 1.25 mm2413ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490082A1140000000000
    M10 × 1.5 mm3017ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490082A1150000000000
    M12 × 1.75 mm3619ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490082A1160000000000
    M14 × 2 mm4222ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490082A1170000000000
    M16 × 2 mm4824ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490082A1180000000000
    M18 × 2.5 mm5427ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490082A1190000000000
    M20 × 2.5 mm6030ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490082A1210000000000
    M24 × 3 mm7236ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490082A1230000000000
    M30 × 3.5 mm9046ISO Class 8
    Fully ThreadedASME B18.2.2, DIN 633490082A1250000000000
     
    High-Strength Steel
    Image of Product. Front orientation. Coupling Nuts. Coupling Nuts.
    Rated Grade 8 or Class 10, these are about 25% stronger than medium-strength steel coupling nuts. Use them with threaded rods that have a comparable 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.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Each
    Thread Size
    Lg.,
    mm
    Wd.,
    mm
    Fastener Strength
    Grade/Class
    Threading
    Specs.
    Met
    1-9
    10-Up
    Zinc-Plated Steel
    M6 × 1 mm1810ISO Class 10
    Fully ThreadedDIN 633490331A5510000000000
    M8 × 1.25 mm2413ISO Class 10
    Fully ThreadedDIN 633490331A55200000000
    M10 × 1.5 mm3017ISO Class 10
    Fully ThreadedDIN 633490331A55300000000
    M12 × 1.75 mm3619ISO Class 10
    Fully ThreadedDIN 633490331A55400000000
    M16 × 2 mm4824ISO Class 10
    Fully ThreadedDIN 633490331A5560000000000
    M20 × 2.5 mm6030ISO Class 10
    Fully ThreadedDIN 633490331A5570000000000
    M24 × 3 mm7236ISO Class 10
    Fully ThreadedDIN 633490331A5580000000000
    M27 × 3 mm8141ISO Class 10
    Fully ThreadedDIN 633490331A5590000000000
    M30 × 3.5 mm9046ISO Class 10
    Fully ThreadedDIN 633490331A55500000000000
     
    Steel
    M8 × 1.25 mm2413ISO Class 10
    Fully ThreadedDIN 633497778A11000000000
    M10 × 1.5 mm3017ISO Class 10
    Fully ThreadedDIN 633497778A12000000000
    M12 × 1.75 mm3619ISO Class 10
    Fully ThreadedDIN 633497778A13000000000
    M16 × 2 mm4824ISO Class 10
    Fully ThreadedDIN 633497778A14000000000
    M20 × 2.5 mm6030ISO Class 10
    Fully ThreadedDIN 633497778A1500000000000
    M24 × 3 mm7236ISO Class 10
    Fully ThreadedDIN 633497778A1600000000000
    M30 × 3.5 mm9046ISO Class 10
    Fully ThreadedDIN 633497778A1700000000000
    M36 × 4 mm10855ISO Class 10
    Fully ThreadedDIN 633497778A180000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Coupling Nuts. Coupling 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.
    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.
    Super-Corrosion-Resistant 316 Stainless Steel—The most corrosion-resistant stainless steel coupling nuts we offer, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Each
    Thread Size
    Lg.,
    mm
    Wd.,
    mm
    Threading
    Specs. Met
    1-9
    10-Up
    18-8 Stainless Steel
    M5 × 0.8 mm158Fully ThreadedDIN 633493590A1050000000000
    M6 × 1 mm1810Fully ThreadedDIN 633493590A10600000000
    M8 × 1.25 mm2413Fully ThreadedDIN 633493590A10700000000
    M10 × 1.5 mm3017Fully ThreadedDIN 633493590A10800000000
    M12 × 1.75 mm3619Fully ThreadedDIN 633493590A10900000000
    M14 × 2 mm4222Fully ThreadedASME B18.2.2, DIN 633493590A3110000000000
    M16 × 2 mm4824Fully ThreadedDIN 633493590A1120000000000
    M18 × 2.5 mm5427Fully ThreadedASME B18.2.2, DIN 633493590A3120000000000
    M20 × 2.5 mm6030Fully ThreadedDIN 633493590A1130000000000
    M22 × 2.5 mm6632Fully ThreadedASME B18.2.2, DIN 633493590A3130000000000
    M24 × 3 mm7236Fully ThreadedASME B18.2.2, DIN 633493590A3140000000000
    M30 × 3.5 mm9046Fully ThreadedASME B18.2.2, DIN 633493590A3160000000000
    M33 × 3.5 mm9950Fully ThreadedDIN 633493590A33600000000000
    M36 × 4 mm10855Fully ThreadedDIN 633493590A337000000000000
     
    Black-Oxide 18-8 Stainless Steel
    M5 × 0.8 mm158Fully ThreadedASME B18.2.2, DIN 633493590A32200000000
    M6 × 1 mm1810Fully ThreadedASME B18.2.2, DIN 633493590A32300000000
    M8 × 1.25 mm2413Fully ThreadedASME B18.2.2, DIN 633493590A324000000000
    M10 × 1.5 mm3017Fully ThreadedASME B18.2.2, DIN 633493590A3250000000000
    M12 × 1.75 mm3619Fully ThreadedASME B18.2.2, DIN 633493590A3260000000000
    M14 × 2 mm4222Fully ThreadedASME B18.2.2, DIN 633493590A3270000000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    M5 × 0.8 mm158Fully ThreadedDIN 633490111A33100000000
    M6 × 1 mm1810Fully ThreadedDIN 633490111A33200000000
    M8 × 1.25 mm2413Fully ThreadedDIN 633490111A33300000000
    M10 × 1.5 mm3017Fully ThreadedDIN 633490111A33400000000
    M12 × 1.75 mm3619Fully ThreadedDIN 633490111A335000000000
    M14 × 2 mm4222Fully ThreadedDIN 633490111A3410000000000
    M16 × 2 mm4824Fully ThreadedDIN 633490111A3360000000000
    M18 × 2.5 mm5427Fully ThreadedDIN 633490111A3370000000000
    M20 × 2.5 mm6030Fully ThreadedDIN 633490111A3380000000000
    M24 × 3 mm7236Fully ThreadedDIN 633490111A3400000000000
     
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