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    133 Products

    Round Coupling Nuts

    Less bulky than hex coupling nuts, these have a smooth, round body that fits in tight spots. Their finished appearance makes them a common choice for decorative applications. Tighten by hand, or use soft-jaw pliers to avoid marring the outside surface. Also known as extension nuts, they are commonly used to connect lengths of threaded rod and join threaded parts.
    Steel
    Image of Product. Front orientation. Coupling Nuts. Round Coupling Nuts.
    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.
    OD
    Threading
    Specs.
    Met
    Certificate Type
    1-9
    10-Up
    Black-Oxide Steel
    5/16"-18
    2"27/64"Fully ThreadedASTM A108Material Certificate
    96177A28000000000000
    5/16"-24
    2"27/64"Fully ThreadedASTM A108Material Certificate
    96177A2900000000000
    3/8"-16
    2"31/64"Fully ThreadedASTM A108Material Certificate
    96177A420000000000
    3/8"-24
    2"31/64"Fully ThreadedASTM A108Material Certificate
    96177A430000000000
    1/2"-13
    2"37/64"Fully ThreadedASTM A108Material Certificate
    96177A510000000000
    1/2"-20
    2"37/64"Fully ThreadedASTM A10896177A5200000000000
    5/8"-11
    2"55/64"Fully ThreadedASTM A108Material Certificate
    96177A5700000000000
    5/8"-18
    2"55/64"Fully ThreadedASTM A10896177A5800000000000
    3/4"-10
    2"63/64"Fully ThreadedASTM A108Material Certificate
    96177A6300000000000
    3/4"-16
    2"63/64"Fully ThreadedASTM A10896177A6400000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Coupling Nuts. Round 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.
    Highly 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.
    OD
    Threading
    Specs.
    Met
    Certificate Type
    1-9
    10-Up
    18-8 Stainless Steel
    5/16"-18
    2"27/64"Fully ThreadedASTM A582Material Certificate
    90202A21800000000000
    5/16"-24
    2"27/64"Fully ThreadedASTM A582Material Certificate
    90202A2190000000000
    3/8"-16
    2"31/64"Fully ThreadedASTM A582Material Certificate
    90202A232000000000
    3/8"-24
    2"31/64"Fully ThreadedASTM A582Material Certificate
    90202A2330000000000
    1/2"-13
    2"37/64"Fully ThreadedASTM A582Material Certificate
    90202A2410000000000
    1/2"-20
    2"37/64"Fully ThreadedASTM A582Material Certificate
    90202A2420000000000
    5/8"-11
    2"55/64"Fully ThreadedASTM A582Material Certificate
    90202A2470000000000
    3/4"-10
    2"63/64"Fully ThreadedASTM A582Material Certificate
    90202A2540000000000
    3/4"-16
    2"63/64"Fully ThreadedASTM A582Material Certificate
    90202A2550000000000
    M14 × 2 mm30 mm18 mmFully ThreadedASTM A582Material Certificate
    90202A1160000000000
    M14 × 2 mm40 mm18 mmFully ThreadedASTM A58290202A1170000000000
    M16 × 2 mm30 mm22 mmFully ThreadedASTM A58290202A1180000000000
    M16 × 2 mm40 mm22 mmFully Threaded90202A44500000000
    M16 × 2 mm50 mm22 mmFully ThreadedASTM A582Material Certificate
    90202A1190000000000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    5/16"-18
    2"27/64"Fully ThreadedASTM A27693282A2800000000000
    5/16"-24
    2"27/64"Fully ThreadedASTM A276Material Certificate
    93282A2900000000000
    3/8"-16
    2"31/64"Fully ThreadedASTM A276Material Certificate
    93282A4200000000000
    1/2"-13
    2"37/64"Fully ThreadedASTM A27693282A5100000000000
    5/8"-11
    2"55/64"Fully ThreadedASTM A276Material Certificate
    93282A5700000000000
    3/4"-10
    2"63/64"Fully ThreadedASTM A276Material Certificate
    93282A6300000000000
     

    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.
    Wd.
    Threading
    Specs.
    Met
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    2"-4 1/2
    4 1/2"2 3/4"Fully Threaded90264A310000000000000000000
    M2 × 0.4 mm6 mm4.5 mmFully Threaded93355A510000000000000
    M14 × 2 mm42 mm22 mmFully ThreadedDIN 633493355A370000000000000
    M16 × 2 mm48 mm24 mmFully ThreadedDIN 633493355A380000000000000
     
    Black-Oxide Steel
    M2 × 0.4 mm6 mm4.5 mmFully Threaded93020A101000000000000
    M16 × 2 mm40 mm27 mmFully Threaded93020A786000000000000
     
    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
    Certificate Type
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    M14 × 2 mm4222Class 8
    Fully ThreadedASME B18.2.2, DIN 633490009A232000000000000000000
    M16 × 2 mm4824Class 8
    Fully ThreadedDIN 633490009A225000000000000
     
    Black-Oxide Steel
    M14 × 2 mm4222Class 8
    Fully ThreadedASME B18.2.2, DIN 633490082A117000000000000000
    M16 × 2 mm4824Class 8
    Fully ThreadedASME B18.2.2, DIN 6334Material Certificate
    90082A118000000000000000
     
    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
    Certificate Type
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    M16 × 2 mm4824Class 10
    Fully ThreadedDIN 633490331A556000000000000000000
     
    Steel
    M16 × 2 mm4824Class 10
    Fully ThreadedDIN 6334Material Certificate
    97778A140000000000000
     
    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.
    Highly 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.
    Wd.
    Threading
    Specs. Met
    Certificate Type
    1-9
    10-49
    50-Up
    18-8 Stainless Steel
    2-56
    5/16"3/16"Fully ThreadedMaterial Certificate
    90268A203000000000000000
    2"-4 1/2
    6"3 1/8"Fully ThreadedMaterial Certificate
    90268A515000000000000000000
    M2 × 0.4 mm6 mm4 mmFully ThreadedMaterial Certificate
    93590A101000000000000
    M14 × 2 mm42 mm22 mmFully ThreadedASME B18.2.2, DIN 633493590A311000000000000000
    M16 × 2 mm48 mm24 mmFully ThreadedDIN 6334Material Certificate
    93590A11200000000000000
     
    Black-Oxide 18-8 Stainless Steel
    M2 × 0.4 mm6 mm4 mmFully Threaded93590A317000000000000
    M14 × 2 mm42 mm22 mmFully ThreadedASME B18.2.2, DIN 6334Material Certificate
    93590A327000000000000000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    2-56
    3/8"1/4"Fully ThreadedMaterial Certificate
    90104A102000000000000
    M14 × 2 mm42 mm22 mmFully ThreadedDIN 6334Material Certificate
    90111A341000000000000000
    M16 × 2 mm48 mm24 mmFully ThreadedDIN 6334Material Certificate
    90111A336000000000000000
     

    Coupling Nuts with Sight Hole

    Image of Product. Front orientation. Coupling Nuts. Coupling Nuts with Sight Hole.
    Confirm that threads are fastened to the right depth at a glance. If you see threads through the sight hole, you'll know that they are properly engaged to ensure a strong hold. Also known as extension nuts, these are commonly used to connect lengths of threaded rod and join threaded parts.
    Low-Strength Steel
    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.
    Each
    Thread
    Size
    Lg.
    Wd.
    Fastener Strength
    Grade/Class
    Threading
    Sight Hole
    Dia.
    1-9
    10-Up
    Zinc-Plated Steel
    8-32
    5/8"5/16"SAE Grade 2
    Fully Threaded1/16"93525A2770000000000
    10-24
    3/4"5/16"SAE Grade 2
    Fully Threaded5/64"93525A28000000000
    10-32
    3/4"5/16"SAE Grade 2
    Fully Threaded5/64"93525A28300000000
    1/4"-20
    3/4"3/8"SAE Grade 2
    Fully Threaded3/32"93525A28600000000
    1/4"-28
    3/4"3/8"SAE Grade 2
    Fully Threaded3/32"93525A28900000000
    5/16"-18
    15/16"1/2"SAE Grade 2
    Fully Threaded3/32"93525A29200000000
    3/8"-16
    1 1/8"9/16"SAE Grade 2
    Fully Threaded1/8"93525A30100000000
    3/8"-24
    1 1/8"9/16"SAE Grade 2
    Fully Threaded1/8"93525A29800000000
    1/2"-13
    1 1/2"3/4"SAE Grade 2
    Fully Threaded3/16"93525A30800000000
    5/8"-11
    1 7/8"15/16"SAE Grade 2
    Fully Threaded3/16"93525A31500000000
    3/4"-10
    2 1/4"1 1/8"SAE Grade 2
    Fully Threaded3/16"93525A32200000000
    1"-8
    3"1 1/2"SAE Grade 2
    Fully Threaded1/4"93525A3290000000000
     

    Miniature Splined Press-Fit Threaded Standoffs

    Image of Product. Front orientation. Standoffs. Miniature Splined Press-Fit Threaded Standoffs.
    Image of Attribute. Front orientation. Contains Annotated. Standoffs. Miniature Splined Press-Fit Threaded Standoffs.
    Image of Attribute. Fully Threaded. Front orientation. Contains Annotated. Standoffs. Miniature Splined Press-Fit Threaded Standoffs.

    Fully

    Threaded

    The smallest standoffs we offer. These press into unthreaded holes to create permanent connections without welding, tapping, or installing extra hardware. The raised splines prevent rotation, and a recessed head clinches material for a strong hold. A through hole allows installation from one side, making them ideal for compact electronics like laptops and handheld devices.
    Wear-Resistant 400 Series Stainless Steel—These standoffs can grind against metal surfaces without denting or scratching. More corrosion resistant than steel.
    Lg.
    OD
    Threading
    Thread
    Lg.
    For Hole
    Dia.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Wear-Resistant 400 Series Stainless Steel
     
    2-56
    3/32"0.124"Fully Threaded3/32"0.125"ASTM A3802592985A81300000
    1/8"0.124"Fully Threaded1/8"0.125"ASTM A3802592985A8140000
     
    M1 × 0.25 mm
    2 mm2.4 mmFully Threaded2 mm2.4 mmASTM A3802592985A81500000
     
    M1.2 × 0.25 mm
    2 mm2.4 mmFully Threaded2 mm2.4 mmASTM A3801092985A2200000
     
    M1.4 × 0.3 mm
    2 mm2.4 mmFully Threaded2 mm2.4 mmASTM A3801092985A2400000
     
    M1.6 × 0.35 mm
    2 mm2.4 mmFully Threaded2 mm2.4 mmASTM A3802592985A2600000
     
    M2 × 0.4 mm
    2 mm3.2 mmFully Threaded2 mm3.2 mmASTM A3802592985A8170000
    3 mm3.2 mmFully Threaded3 mm3.2 mmASTM A3802592985A8180000
     

    Female Threaded Hex Standoffs

    Image of Product. Front orientation. Standoffs. Female Threaded Hex Standoffs.
    Image of Attribute. Front orientation. Contains Annotated. Standoffs. Female Threaded Hex Standoffs.
    Image of Attribute. Fully Threaded. Front orientation. Contains Annotated. Fully Threaded. Female Threaded Hex Standoffs.

    Fully

    Threaded

    Stack male-threaded components and create a clean, flush connection between them. To securely tighten standoffs, grip the flat sides of the hex body with a wrench.
    Corrosion-Resistant 18-8 Stainless Steel—The choice for wet and outdoor environments, these standoffs resist rusting. They're strong enough for most jobs, but won't withstand stress as well as steel.
    Zinc-Plated Carbon Steel—Best for dry environments since moisture will cause these standoffs to rust.
    Each
    Lg.
    Hex
    Size
    Threading
    Thread
    Lg.
    Specs. Met
    1-99
    100-499
    500-Up
    Corrosion-Resistant 18-8 Stainless Steel
     
    2-56
    1/16"1/8"Fully Threaded1/16"ASTM A581/A58291115A934000000000000000
    1/8"1/8"Fully Threaded1/8"ASTM A58291115A802000000000000
    1/8"3/16"Fully Threaded1/8"ASTM A581/A58291115A101000000000000
    5/32"1/8"Fully Threaded5/32"ASTM A581/A58291115A935000000000000
    5/32"3/16"Fully Threaded5/32"ASTM A581/A58291115A001000000000000
    3/16"1/8"Fully Threaded3/16"ASTM A58291115A804000000000000
    3/16"3/16"Fully Threaded3/16"ASTM A581/A58291115A102000000000000
    7/32"1/8"Fully Threaded7/32"ASTM A581/A58291115A936000000000000
    7/32"3/16"Fully Threaded7/32"ASTM A581/A58291115A002000000000000
    1/4"1/8"Fully Threaded1/4"ASTM A58291115A806000000000000
    1/4"3/16"Fully Threaded1/4"ASTM A581/A58291115A103000000000000
    9/32"1/8"Fully Threaded9/32"ASTM A58291115A808000000000000
    9/32"3/16"Fully Threaded9/32"ASTM A581/A58291115A003000000000000
    5/16"1/8"Fully Threaded5/16"ASTM A58291115A810000000000000
    5/16"3/16"Fully Threaded5/16"ASTM A581/A58291115A104000000000000
    11/32"1/8"Fully Threaded11/32"ASTM A581/A58291115A944000000000000
    11/32"3/16"Fully Threaded11/32"ASTM A581/A58291115A005000000000000
    3/8"1/8"Fully Threaded3/8"ASTM A58291115A812000000000000
    3/8"3/16"Fully Threaded3/8"ASTM A581/A58291115A105000000000000
    13/32"1/8"Fully Threaded13/32"ASTM A581/A58291115A945000000000000
    13/32"3/16"Fully Threaded13/32"ASTM A581/A58291115A006000000000000
    7/16"3/16"Fully Threaded7/16"ASTM A581/A58291115A007000000000000
    15/32"1/8"Fully Threaded15/32"ASTM A581/A58291115A946000000000000
    15/32"3/16"Fully Threaded15/32"ASTM A581/A58291115A008000000000000
    1/2"3/16"Fully Threaded1/2"ASTM A581/A58291115A107000000000000
    9/16"1/8"Fully Threaded9/16"ASTM A581/A58291115A954000000000000
    5/8"1/8"Fully Threaded5/8"ASTM A581/A58291115A955000000000000
    5/8"3/16"Fully Threaded5/8"ASTM A581/A58291115A109000000000000
     
    Zinc-Plated Carbon Steel
     
    2-56
    1/8"1/8"Fully Threaded1/8"91920A002000000000000
    1/8"3/16"Fully Threaded1/8"91920A101000000000000
    5/32"3/16"Fully Threaded5/32"91920A912000000000000
    3/16"1/8"Fully Threaded3/16"91920A004000000000000
    3/16"3/16"Fully Threaded3/16"91920A102000000000000
    7/32"3/16"Fully Threaded7/32"91920A913000000000000
    1/4"1/8"Fully Threaded1/4"91920A006000000000000
    1/4"3/16"Fully Threaded1/4"91920A103000000000000
    9/32"1/8"Fully Threaded9/32"91920A008000000000000
    9/32"3/16"Fully Threaded9/32"91920A914000000000000
    5/16"1/8"Fully Threaded5/16"91920A010000000000000
    5/16"3/16"Fully Threaded5/16"91920A104000000000000
    11/32"3/16"Fully Threaded11/32"91920A916000000000000
    3/8"1/8"Fully Threaded3/8"91920A012000000000000
    3/8"3/16"Fully Threaded3/8"91920A105000000000000
    13/32"3/16"Fully Threaded13/32"91920A917000000000000
    7/16"1/8"Fully Threaded7/16"91920A014000000000000
    7/16"3/16"Fully Threaded7/16"91920A918000000000000
    15/32"3/16"Fully Threaded15/32"91920A919000000000000
    1/2"1/8"Fully Threaded1/2"91920A016000000000000
    1/2"3/16"Fully Threaded1/2"91920A107000000000000
    5/8"3/16"Fully Threaded5/8"91920A111000000000000
    3/4"3/16"Fully Threaded3/4"91920A113000000000000
     

    Sanitary Female Threaded Standoffs

    Image of Product. Front orientation. Standoffs. Sanitary Female Threaded Standoffs.
    Image of Product. Back orientation. Standoffs. Sanitary Female Threaded Standoffs.
    Image of Attribute. Fully Threaded. Front orientation. Contains Annotated. Standoffs. Sanitary Female Threaded Standoffs.

    Fully

    Threaded

    Mount male-threaded components onto food processing lines, walls, and sanitary equipment, while leaving space to clean in between. The smooth finish and rounded edges eliminate pits or crevices where bacteria could grow. These standoffs stand up to hard cleaners and detergents and won't corrode from frequent washdowns. A rubber seal stops water and contaminants from entering the body of these standoffs. They are FDA compliant for safe contact with food.
    304 Stainless Steel—Resist corrosion in environments exposed to moisture, chemicals, or frequent cleaning.
    Silicone Rubber Seal—Withstand the widest temperature range of any rubber seal we offer. These standoffs resist detergents but break down when exposed to oil, grease, and fuel.
    Lg.
    OD
    Threading
    Thread
    Lg.
    Temp. Range,
    ° F
    Seal Material
    Food Industry Std.
    Each
    304 Stainless Steel
     
    1/4"-20 UNC
    2"1 3/16"Fully Threaded2"-75 to 390Silicone Rubber
    FDA Compliant 21 CFR 177.2600
    93531A113000000
     
    3/8"-16 UNC
    2"1 3/16"Fully Threaded2"-75 to 390Silicone Rubber
    FDA Compliant 21 CFR 177.2600
    93531A11200000
     

    Female Threaded Round Standoffs

    Image of Product. Front orientation. Standoffs. Female Threaded Round Standoffs.
    Image of Attribute. Fully Threaded. Front orientation. Contains Annotated. Fully Threaded. Female Threaded Round Standoffs.

    Fully

    Threaded

    Stack male-threaded components and create a clean, flush connection between them.
    Corrosion-Resistant 18-8 Stainless Steel—The choice for wet and outdoor environments, these standoffs resist rusting. They're strong enough for most jobs, but won't withstand stress as well as steel.
    Zinc-Plated Carbon Steel—Best for dry environments since moisture will cause these standoffs to rust.
    Each
    Lg.
    OD
    Threading
    Thread
    Lg.
    Specs. Met
    1-99
    100-499
    500-Up
    Corrosion-Resistant 18-8 Stainless Steel
     
    2-56
    1/4"1/8"Fully Threaded1/4"ASTM A581/A58291125A010000000000000000
    5/16"1/8"Fully Threaded5/16"ASTM A581/A58291125A014000000000000
    3/8"1/8"Fully Threaded3/8"ASTM A581/A58291125A018000000000000
    1/2"1/8"Fully Threaded1/2"ASTM A581/A58291125A026000000000000
     
    Zinc-Plated Carbon Steel
     
    2-56
    1/4"1/8"Fully Threaded1/4"93265A010000000000000
    5/16"1/8"Fully Threaded5/16"93265A014000000000000
    3/8"1/8"Fully Threaded3/8"93265A018000000000000
    1/2"1/8"Fully Threaded1/2"93265A026000000000000
     
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