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    53 Products

    Thin-Heavy-Profile Nylon-Insert Locknuts

    About half the height of standard-profile locknuts and 10% wider, these fit in spaces with low clearance and handle heavier loads by distributing them over a larger area. You can also use them as jam nuts by threading them against a hex nut to hold it in place. 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. Thin-Heavy-Profile 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.
    Black-Phosphate-Coated Steel—The dark coating creates both a finished appearance and a barrier against rust that's comparable to zinc yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Each
    Black-Phosphate-Coated Steel
    1 1/4"-12
    2"1 7/64"ASTM Grade C
    25000000000000000
    1 1/2"-12
    2 3/8"1 5/16"ASTM Grade C
    25000000000000000
    1 3/4"-12
    2 3/4"1 15/32"ASTM Grade C
    25000000000000000
    2"-12
    3 1/8"1 43/64"ASTM Grade C
    25000000000000000
    2 1/4"-12
    3 1/2"1 15/16"ASTM Grade C
    25000000000000000
    2 1/2"-12
    4"2 3/16"ASTM Grade C
    25000000000000000
    2 3/4"-12
    4"2 3/16"ASTM Grade C
    25000000000000000
    3"-12
    4 1/2"2 41/64"ASTM Grade C
    250000000000000000
     

    Top-Lock Distorted-Thread Locknuts

    Irregularly shaped threads at the top of these locknuts grip the screw for a stronger hold than nylon-insert locknuts. Although the threads prevent the nut from backing out due to vibration, they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch. Nuts are not reusable.
    High-Strength Steel
    Image of Product. Front orientation. Locknuts. Top-Lock Distorted-Thread 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.
    Black-Phosphate-Coated Steel—The dark coating creates both a finished appearance and a barrier against rust that's comparable to zinc yellow-chromate plating.
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Black-Phosphate-Coated Steel
    M5 × 0.8 mm85.1ISO Class 10
    50000000000000000
    M6 × 1 mm106ISO Class 10
    250000000000000
    M8 × 1 mm138ISO Class 10
    100000000000000
    M8 × 1.25 mm138ISO Class 10
    2500000000000000
    M10 × 1.25 mm1710ISO Class 10
    500000000000000
    M10 × 1.5 mm1710ISO Class 10
    1000000000000000
    M12 × 1.25 mm1912ISO Class 10
    500000000000000
    M12 × 1.5 mm1912ISO Class 10
    500000000000000
    M12 × 1.75 mm1912ISO Class 10
    50000000000000
    M14 × 1.5 mm2214ISO Class 10
    500000000000000
    M14 × 2 mm2214ISO Class 10
    500000000000000
    M16 × 1.5 mm2416ISO Class 10
    10000000000000
    M16 × 2 mm2416ISO Class 10
    500000000000000
    M20 × 2.5 mm3020ISO Class 10
    10000000000000
    M22 × 1.5 mm3322ISO Class 10
    10000000000000
    M22 × 2.5 mm3322ISO Class 10
    10000000000000
     

    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.
    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.
    Black Phosphate-Coated Steel—The dark coating creates both a finished appearance and a barrier against rust that's more durable than clear zinc plating.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Black Phosphate-Coated Steel
    1/4"-20
    7/16"15/64"19/32"0.04"SAE Grade 8
    5000000000000000
    5/16"-18
    1/2"9/32"11/16"0.04"SAE Grade 8
    250000000000000
    3/8"-16
    9/16"11/32"3/4"0.04"SAE Grade 8
    250000000000000
     

    Distorted-Thread Flange Nuts

    The strongest hold of all the flange nuts we offer, these have irregularly shaped threads that grip the screw to resist loosening. The threads prevent the nut from backing out due to high vibration, but they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch, so they are not reusable. Nuts have a flange that distributes pressure evenly across the mounting surface without the need for a separate washer. 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. Bottom orientation. Flange Nuts. Distorted-Thread 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.
    Black Phosphate-Coated Steel—The dark coating creates both a finished appearance and a barrier against rust that's more durable than clear zinc plating.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Black Phosphate-Coated Steel
    1/4"-20
    7/16"15/64"9/16"0.05"SAE Grade 5
    10000000000000000
    5/16"-18
    1/2"9/32"11/16"0.05"SAE Grade 5
    10000000000000000
    3/8"-16
    9/16"11/32"3/4"0.06"SAE Grade 5
    10000000000000000
    7/16"-14
    11/16"25/64"15/16"0.06"SAE Grade 5
    5000000000000000
    7/16"-20
    11/16"25/64"15/16"0.06"SAE Grade 5
    5000000000000000
    1/2"-13
    3/4"29/64"1 1/32"0.08"SAE Grade 5
    5000000000000000
    1/2"-20
    3/4"29/64"1 1/32"0.08"SAE Grade 5
    5000000000000000
    5/8"-11
    15/16"9/16"1 9/32"0.09"SAE Grade 5
    100000000000000
    3/4"-10
    1 1/8"43/64"1 37/64"0.11"SAE Grade 5
    1000000000000000
    1"-8
    1 1/2"29/32"2 1/16"0.13"SAE Grade 5
    10000000000000
     
    High-Strength Steel
    Image of Product. Bottom orientation. Flange Nuts. Distorted-Thread 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.
    Black Phosphate-Coated Steel—The dark coating creates both a finished appearance and a barrier against rust that's more durable than clear zinc plating.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Black Phosphate-Coated Steel
    1/4"-20
    7/16"19/64"9/16"0.04"ASME Grade G
    10000000000000000
    1/4"-28
    7/16"19/64"9/16"0.04"ASME Grade G
    1000000000000000
    5/16"-18
    1/2"23/64"11/16"0.05"ASME Grade G
    10000000000000000
    5/16"-24
    1/2"23/64"11/16"0.05"ASME Grade G
    10000000000000000
    3/8"-16
    9/16"27/64"13/16"0.06"ASME Grade G
    5000000000000000
    3/8"-24
    9/16"27/64"13/16"0.06"ASME Grade G
    2500000000000000
    1/2"-13
    3/4"9/16"1 1/16"0.08"ASME Grade G
    2500000000000000
    1/2"-20
    3/4"9/16"1 1/16"0.08"ASME Grade G
    250000000000000
    5/8"-11
    15/16"11/16"1 21/64"0.1"ASME Grade G
    1000000000000000
    5/8"-18
    15/16"11/16"1 21/64"0.1"ASME Grade G
    100000000000000
    3/4"-10
    1 1/8"53/64"1 37/64"0.11"ASME Grade G
    1000000000000000
    3/4"-16
    1 1/8"53/64"1 37/64"0.11"ASME Grade G
    100000000000000
    7/8"-9
    1 5/16"51/64"1 3/4"0.12"ASME Grade G
    500000000000000
    7/8"-14
    1 5/16"51/64"1 3/4"0.12"ASME Grade G
    500000000000000
    1"-8
    1 1/2"57/64"2 1/16"0.13"ASME Grade G
    500000000000000
    1"-14
    1 1/2"57/64"2 1/16"0.13"ASME Grade G
    500000000000000
     
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