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    110 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.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    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
    		25093126A11000000
    1 1/2"-12
    		2 3/8"1 5/16"ASTM Grade C
    		25093126A12000000
    1 3/4"-12
    		2 3/4"1 15/32"ASTM Grade C
    		25093126A13000000
    2"-12
    		3 1/8"1 43/64"ASTM Grade C
    		25093126A14000000
    2 1/4"-12
    		3 1/2"1 15/16"ASTM Grade C
    		25093126A15000000
    2 1/2"-12
    		4"2 3/16"ASTM Grade C
    		25093126A16000000
    2 3/4"-12
    		4"2 3/16"ASTM Grade C
    		25093126A17000000
    3"-12
    		4 1/2"2 41/64"ASTM Grade C
    		25093126A210000000
     
    Steel
    1 1/8"-12
    		1 7/8"1"ASTM Grade C
    		25093126A18000000
    1 3/8"-12
    		2 13/64"1 3/16"ASTM Grade C
    		25093126A19000000
     
    Low-Strength Steel
    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile Nylon-Insert Locknuts.
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar 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-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.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    		1/2"9/32"25010090652A029000000
    5/16"-18
    		9/16"5/16"25010090652A03000000
    3/8"-16
    		11/16"13/32"2505090652A04000000
    1/2"-13
    		7/8"17/32"2502590652A05000000
    5/8"-11
    		1 1/16"39/64"2501090652A05500000
    3/4"-10
    		1 1/4"45/64"2501090652A06000000
    1"-8
    		1 5/8"57/64"250190652A0650000
    1 1/4"-7
    		2"1 7/64"250190652A0700000
     
    Black-Corrosion-Resistant-Coated Steel
    1/4"-20
    		1/2"9/32"250590652A8100000
    5/16"-18
    		9/16"5/16"250590652A8200000
    3/8"-16
    		11/16"13/32"250190652A8300000
    1/2"-13
    		7/8"17/32"250190652A8400000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile 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.
    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.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/4"-20
    		1/2"9/32"2502590098A110000000
    5/16"-18
    		9/16"5/16"2502090098A11500000
    3/8"-16
    		11/16"13/32"2501090098A12000000
    1/2"-13
    		7/8"17/32"250190098A1300000
    5/8"-11
    		1 1/16"5/8"250190098A0350000
    3/4"-10
    		1 1/4"45/64"250190098A03600000
    1"-8
    		1 5/8"59/64"250190098A13500000
     
    316 Stainless Steel
    3/8"-16
    		11/16"13/32"250194530A1130000
    1/2"-13
    		7/8"17/32"250194530A1150000
    5/8"-11
    		1 1/16"39/64"250194530A1170000
    3/4"-10
    		1 1/4"45/64"250194530A11900000
     

    Thin-Heavy-Profile Hex Nuts

    About half the height of standard-profile hex nuts 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 another hex nut to hold it in place.
    Extreme-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Thin-Heavy-Profile Hex Nuts.
    These nuts are about 20% stronger than high-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.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    		1/2"11/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194591879A029000000
    5/16"-18
    		9/16"13/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194591879A03000000
    3/8"-16
    		11/16"15/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194591879A03100000
    1/2"-13
    		7/8"19/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194591879A03200000
    5/8"-11
    		1 1/16"23/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194591879A03300000
    3/4"-10
    		1 1/4"27/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194591879A03400000
     
    Steel
    1/4"-20
    		1/2"11/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194195010A1300000
    3/8"-16
    		11/16"15/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194595010A14000000
    7/16"-14
    		3/4"17/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194195010A1450000
    1/2"-13
    		7/8"19/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194595010A15000000
    5/8"-11
    		1 1/16"23/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194195010A1600000
    3/4"-10
    		1 1/4"27/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194195010A1650000
    7/8"-9
    		1 7/16"31/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194195010A1700000
    1"-8
    		1 5/8"35/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194195010A1750000
    1 1/8"-7
    		1 13/16"39/64"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194195010A1800000
    1 1/4"-7
    		2"23/32"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194195010A1900000
    1 3/8"-6
    		2 3/16"25/32"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194195010A3200000
    1 1/2"-6
    		2 3/8"27/32"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194195010A2100000
    1 3/4"-5
    		2 3/4"31/32"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194195010A22000000
    2"-4 1/2
    		3 1/8"1 3/32"ASTM Grade 2H
    		ASME B18.2.2, ASTM A194195010A24000000
     
    Low-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Thin-Heavy-Profile Hex Nuts.
    Rated Grade 2, Class 6, or lower, these nuts are about half as strong as medium-strength nuts. They are suitable for light duty fastening applications, such as securing access panels. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create 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.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Steel
    1/4"-20
    		1/2"11/64"—2591015A02900000
    5/16"-18
    		9/16"13/64"—2591015A0300000
    3/8"-16
    		11/16"15/64"—2591015A03100000
    7/16"-14
    		3/4"17/64"—2591015A03200000
    1/2"-13
    		7/8"19/64"—1091015A0330000
    5/8"-11
    		1 1/16"23/64"—1091015A0350000
    3/4"-10
    		1 1/4"27/64"—591015A0360000
    7/8"-9
    		1 7/16"31/64"—591015A03700000
    1"-8
    		1 5/8"35/64"—191015A0380000
     
    Steel
    1/4"-20
    		1/2"11/64"SAE Grade 2
    		10090502A0290000
    5/16"-18
    		9/16"13/64"SAE Grade 2
    		10090502A0300000
    3/8"-16
    		11/16"15/64"SAE Grade 2
    		10090502A03100000
    7/16"-14
    		3/4"17/64"SAE Grade 2
    		5090502A0320000
    1/2"-13
    		7/8"19/64"SAE Grade 2
    		5090502A03300000
    5/8"-11
    		1 1/16"23/64"SAE Grade 2
    		2590502A41000000
    3/4"-10
    		1 1/4"27/64"SAE Grade 2
    		2590502A41500000
    7/8"-9
    		1 7/16"31/64"SAE Grade 2
    		1090502A42000000
    1"-8
    		1 5/8"35/64"SAE Grade 2
    		1090502A42500000
    1 1/8"-7
    		1 13/16"39/64"SAE Grade 2
    		590502A43000000
    1 1/4"-7
    		2"23/32"SAE Grade 2
    		590502A43500000
    1 1/2"-6
    		2 3/8"27/32"SAE Grade 2
    		190502A4400000
    1 3/4"-5
    		2 3/4"31/32"SAE Grade 2
    		190502A0440000
    2"-4 1/2
    		3 1/8"1 3/32"SAE Grade 2
    		190502A04600000
    2 1/2"-4
    		3 7/8"1 29/64"SAE Grade 2
    		190502A04900000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Hex Nuts. Thin-Heavy-Profile Hex 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.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/4"-20
    		1/2"11/64"2591851A62000000
    5/16"-18
    		9/16"13/64"2091851A0300000
    3/8"-16
    		11/16"15/64"1091851A6300000
    1/2"-13
    		7/8"19/64"1091851A64000000
    5/8"-11
    		1 1/16"23/64"591851A64500000
    3/4"-10
    		1 1/4"27/64"191851A6500000
    7/8"-9
    		1 7/16"31/64"191851A0370000
    1"-8
    		1 5/8"35/64"191851A0380000
    1 1/8"-7
    		1 13/16"39/64"191851A6550000
    1 1/4"-7
    		2"23/32"191851A6600000
    1 1/2"-6
    		2 3/8"27/32"191851A66500000
    1 3/4"-5
    		2 3/4"31/32"191851A67000000
     
    Brass
    Image of Product. Front orientation. Hex Nuts. Thin-Heavy-Profile Hex Nuts.
    Brass—Conductive and nonmagnetic, brass nuts are commonly used to secure electrical equipment, such as circuit board assemblies and mounting brackets, inside enclosures. They're also softer than most metals, so they won't damage other fastening components.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Brass
    1/4"-20
    		1/2"11/64"2592683A02900000
    5/16"-18
    		9/16"13/64"2592683A84000000
    3/8"-16
    		11/16"15/64"2592683A84500000
    7/16"-14
    		3/4"17/64"1092683A8470000
    1/2"-13
    		7/8"19/64"1092683A85500000
    5/8"-11
    		1 1/16"23/64"592683A86000000
    3/4"-10
    		1 1/4"27/64"192683A8650000
    7/8"-9
    		1 7/16"31/64"192683A8690000
    1"-8
    		1 5/8"35/64"192683A8720000
    1 1/8"-7
    		1 13/16"39/64"192683A8790000
    1 1/4"-7
    		2"23/32"192683A88200000
    1 1/2"-6
    		2 3/8"27/32"192683A88500000
     

    Thin-Heavy-Profile Flex-Top Locknuts for Heavy Vibration

    About two-thirds the height of standard flex-top nuts and 10% wider, these fit in spaces with low clearance and handle heavier loads by distributing them over a larger area. Because of the thin profile, you can also use them as jam nuts by threading them against a hex nut to hold it in place. The top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Steel
    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile Flex-Top Locknuts for Heavy Vibration.
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc-yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    1/4"-20
    		1/2"7/32"2594828A410000000
    5/16"-18
    		9/16"17/64"1094828A4200000
    3/8"-16
    		5/8"9/32"1094828A42500000
    7/16"-14
    		3/4"21/64"194828A4300000
    1/2"-13
    		13/16"21/64"594828A43500000
    5/8"-11
    		1"13/32"194828A4400000
    3/4"-10
    		1 1/8"27/64"194828A03600000
    7/8"-9
    		1 5/16"31/64"194828A03700000
    1"-8
    		1 1/2"37/64"194828A03800000
     
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