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Castle Nuts (184 items)

Zoro Select 3/4"-16 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 10 pk. 354245G
Zoro Select

3/4"-16 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 10 pk.

Zoro # G0865566
Mfr # 354245G
product price:  $14.89
/pk 10, $1.49/ea
Zoro Select 5/8"-18 Grade 5 Zinc Plated Finish Steel Round Slotted Castle Nut, 25 pk. 351204G
Zoro Select

5/8"-18 Grade 5 Zinc Plated Finish Steel Round Slotted Castle Nut, 25 pk.

Zoro # G0634803
Mfr # 351204G
product price:  $13.99
/pk 25, $0.56/ea
Zoro Select 5/8"-11 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 25 pk. 351185G
Zoro Select

5/8"-11 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 25 pk.

Zoro # G2056887
Mfr # 351185G
product price:  $12.99
/pk 25, $0.52/ea
Zoro Select 1"-14 Grade 5 Zinc Plated Finish Steel Round Slotted Castle Nut, 5 pk. 351324G
Zoro Select

1"-14 Grade 5 Zinc Plated Finish Steel Round Slotted Castle Nut, 5 pk.

Zoro # G2112232
Mfr # 351324G
product price:  $14.29
/pk 5, $2.86/ea
Zoro Select 1"-12 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 5 pk. 372305G
Zoro Select

1"-12 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 5 pk.

Zoro # G2264534
Mfr # 372305G
product price:  $27.59
/pk 5, $5.52/ea
Zoro Select 3/4"-16 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 10 pk. 351245G
Zoro Select

3/4"-16 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 10 pk.

Zoro # G2564545
Mfr # 351245G
product price:  $8.95
/pk 10, $0.89/ea
Zoro Select 1"-14 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 5 pk. 354315G
Zoro Select

1"-14 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 5 pk.

Zoro # G2748934
Mfr # 354315G
product price:  $12.19
/pk 5, $2.44/ea
Aftermarket Castle Nut OTK20-0324
Aftermarket

Castle Nut

Zoro # G505607633
Mfr # OTK20-0324
product price:  $24.49
/ea
Zoro Select 1"-8 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 5 pk. U12005.100.0001
Zoro Select

1"-8 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 5 pk.

Zoro # G0849746
Mfr # U12005.100.0001
product price:  $28.35
/pk 5, $5.67/ea
Midwest Fastener 7/8"-14 Zinc Plated Steel Fine Thread Castle Hex Nuts 2PK 68544
Midwest Fastener

7/8"-14 Zinc Plated Steel Fine Thread Castle Hex Nuts 2PK

Zoro # G202520310
Mfr # 68544
product price:  $13.45
/pk 2, $6.73/ea
Zoro Select 1-1/2"-12 Grade 5 Zinc Plated Finish Steel Round Slotted Castle Nut, 5 pk. 351480G
Zoro Select

1-1/2"-12 Grade 5 Zinc Plated Finish Steel Round Slotted Castle Nut, 5 pk.

Zoro # G1944923
Mfr # 351480G
product price:  $50.15
/pk 5, $10.03/ea
Zoro Select 1-1/4"-12 Grade 5 Zinc Plated Finish Steel Round Slotted Castle Nut, 5 pk. 351404G
Zoro Select

1-1/4"-12 Grade 5 Zinc Plated Finish Steel Round Slotted Castle Nut, 5 pk.

Zoro # G2687115
Mfr # 351404G
product price:  $21.69
/pk 5, $4.34/ea
Zoro Select Hex Nut, 1-1/4-12, Plain, Grade 5 U12025.125.0001
Zoro Select

Hex Nut, 1-1/4-12, Plain, Grade 5

Zoro # G6600050
Mfr # U12025.125.0001
product price:  $10.15
/ea
Zoro Select 1-1/2"-6 Grade 8 Plain Finish Carbon Steel Round Slotted Castle Nut U12030.150.0001
Zoro Select

1-1/2"-6 Grade 8 Plain Finish Carbon Steel Round Slotted Castle Nut

Zoro # G2520677
Mfr # U12030.150.0001
product price:  $38.59
/ea
Suburban Bolt And Supply M24-2.0 CASTLE NUT A44302400CS
Suburban Bolt And Supply

M24-2.0 CASTLE NUT

Zoro # G803497332
Mfr # A44302400CS
product price:  $22.39
/ea
Zoro Select 1"-8 Grade 2H Plain Finish Steel Round Slotted Castle Nut, 5 pk. 352308G
Zoro Select

1"-8 Grade 2H Plain Finish Steel Round Slotted Castle Nut, 5 pk.

Zoro # G1062187
Mfr # 352308G
product price:  $14.19
/pk 5, $2.84/ea
Zoro Select 1/2"-13 Grade 2 Zinc Plated Finish Low Carbon Steel Round Slotted Castle Nut, 25 pk. 287062-PG
Zoro Select

1/2"-13 Grade 2 Zinc Plated Finish Low Carbon Steel Round Slotted Castle Nut, 25 pk.

Zoro # G0602253
Mfr # 287062-PG
product price:  $19.79
/pk 25, $0.79/ea
Zoro Select 7/8"-14 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 10 pk. 354285G
Zoro Select

7/8"-14 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 10 pk.

Zoro # G3074723
Mfr # 354285G
product price:  $19.55
/pk 10, $1.96/ea
Zoro Select 7/16"-14 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 100 pk. 351075G
Zoro Select

7/16"-14 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 100 pk.

Zoro # G2409811
Mfr # 351075G
product price:  $21.19
/pk 100, $0.21/ea
Zoro Select 9/16"-18 Grade 5 Zinc Plated Finish Steel Round Slotted Castle Nut, 25 pk. 351164G
Zoro Select

9/16"-18 Grade 5 Zinc Plated Finish Steel Round Slotted Castle Nut, 25 pk.

Zoro # G1999365
Mfr # 351164G
product price:  $10.79
/pk 25, $0.43/ea
Zoro Select Castle Nut, Steel, Black Oxide M12000.300.0001
Zoro Select

Castle Nut, Steel, Black Oxide

Zoro # G0302410
Mfr # M12000.300.0001
product price:  $32.69
/pk 5, $6.54/ea
Zoro Select 5/8"-11 Grade 5 Zinc Plated Finish Carbon Steel Round Slotted Castle Nut, 10 pk. U12006.062.0001
Zoro Select

5/8"-11 Grade 5 Zinc Plated Finish Carbon Steel Round Slotted Castle Nut, 10 pk.

Zoro # G2521018
Mfr # U12006.062.0001
product price:  $18.89
/pk 10, $1.89/ea
Zoro Select Castle Nut, Steel, Black Oxide M12020.240.0150
Zoro Select

Castle Nut, Steel, Black Oxide

Zoro # G9900801
Mfr # M12020.240.0150
product price:  $84.59
/pk 10, $8.46/ea
Zoro Select 5/8"-18 Grade 2 Zinc Plated Finish Low Carbon Steel Round Slotted Castle Nut, 25 pk. SNFI20620-025P
Zoro Select

5/8"-18 Grade 2 Zinc Plated Finish Low Carbon Steel Round Slotted Castle Nut, 25 pk.

Zoro # G1153634
Mfr # SNFI20620-025P
product price:  $11.99
/pk 25, $0.48/ea
Zoro Select 3/8"-24 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 100 pk. 371065G
Zoro Select

3/8"-24 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 100 pk.

Zoro # G2322442
Mfr # 371065G
product price:  $44.89
/pk 100, $0.45/ea
Zoro Select 1-1/4"-7 Grade 5 Plain Finish Carbon Steel Round Slotted Castle Nut U12005.125.0001
Zoro Select

1-1/4"-7 Grade 5 Plain Finish Carbon Steel Round Slotted Castle Nut

Zoro # G2521097
Mfr # U12005.125.0001
product price:  $14.39
/ea
Zoro Select 7/8"-14 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 10 pk. 351285G
Zoro Select

7/8"-14 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 10 pk.

Zoro # G1312026
Mfr # 351285G
product price:  $15.39
/pk 10, $1.54/ea
Zoro Select 1-1/8"-12 Grade 5 Zinc Plated Finish Steel Round Slotted Castle Nut, 5 pk. 351367G
Zoro Select

1-1/8"-12 Grade 5 Zinc Plated Finish Steel Round Slotted Castle Nut, 5 pk.

Zoro # G1252002
Mfr # 351367G
product price:  $17.79
/pk 5, $3.56/ea
Midwest Fastener 12mm-1.25 Zinc Plated Class 8 Steel Extra Fine Thread Castle Nuts 6PK 76231
Midwest Fastener

12mm-1.25 Zinc Plated Class 8 Steel Extra Fine Thread Castle Nuts 6PK

Zoro # G002521609
Mfr # 76231
product price:  $37.15
/pk 6, $6.19/ea
Zoro Select 1"-14 Grade 2 Zinc Plated Finish Low Carbon Steel Round Slotted Castle Nut, 10 pk. SNFI21000-010P
Zoro Select

1"-14 Grade 2 Zinc Plated Finish Low Carbon Steel Round Slotted Castle Nut, 10 pk.

Zoro # G2851886
Mfr # SNFI21000-010P
product price:  $18.39
/pk 10, $1.84/ea
Zoro Select 1-1/8"-12 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 5 pk. 371365G
Zoro Select

1-1/8"-12 Grade 5 Plain Finish Steel Round Slotted Castle Nut, 5 pk.

Zoro # G2163497
Mfr # 371365G
product price:  $24.49
/pk 5, $4.90/ea
Zoro Select 7/8-14 CASTLE NUTS ZINC, PK60 88NHC
Zoro Select

7/8-14 CASTLE NUTS ZINC, PK60

Zoro # G2442052
Mfr # 88NHC
product price:  $274.99
/pk 60, $4.58/ea
Suburban Bolt And Supply 7/8-14 CASTLE NUT A04305600CS
Suburban Bolt And Supply

7/8-14 CASTLE NUT

Zoro # G603497631
Mfr # A04305600CS
product price:  $1.55
/ea
Sold in mult. of 20 for $31.00
Huyett Slotted Locking Hex Nut 1-1/2x1-9/32 Steel Plain NUTH00-1500-1281SP
Huyett

Slotted Locking Hex Nut 1-1/2x1-9/32 Steel Plain

Zoro # G113331166
Mfr # NUTH00-1500-1281SP
product price:  $5.15
/ea
Sold in mult. of 4 for $20.60
Zoro Select 1-3/4"-5 Grade 2H Plain Finish Steel Round Slotted Castle Nut, 5 pk. 352538G
Zoro Select

1-3/4"-5 Grade 2H Plain Finish Steel Round Slotted Castle Nut, 5 pk.

Zoro # G1784036
Mfr # 352538G
product price:  $79.19
/pk 5, $15.84/ea
Zoro Select 3/8"-16 Grade 2 Zinc Plated Finish Low Carbon Steel Round Slotted Castle Nut, 50 pk. 287054-PG
Zoro Select

3/8"-16 Grade 2 Zinc Plated Finish Low Carbon Steel Round Slotted Castle Nut, 50 pk.

Zoro # G1101204
Mfr # 287054-PG
product price:  $20.19
/pk 50, $0.40/ea
Castle Nuts (184 items)
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About Castle Nuts

Castle nuts are a type of fastener that is used to secure two or more parts together. They are often used in conjunction with bolts, screws, and other types of fasteners to create a secure connection.

Types of Castle Nuts

Castle nuts come in a variety of shapes and sizes depending on their intended use. Slotted castle nuts are commonly used for applications where vibration is an issue, while non-slotted versions are better suited for applications where security is paramount. Many slotted nut manufacturers offer custom designs to meet specific needs.

How Castle Nuts Are Made

Castle nuts are typically made from metal alloys such as steel or brass, but can also be made from other materials such as aluminum or plastic depending on the application requirements. The manufacturing process involves cutting threads into the material and then forming the castle shape around it before adding additional features like slots.

Industries That Use Castle Nuts

Castle nuts are commonly used by professionals in industries such as automotive, construction, aerospace engineering, and robotics due to their ability to securely connect components together without coming loose over time. Wherever high levels of security and reliability are needed when connecting two or more parts together, you will likely find castle nuts being used.

Find the Castle Nuts You Need at Zoro

Looking for a specific item? Use our robust search tool to find it by name or keyword, or use our handy filters to narrow down our full assortment. You can also check out our whole selection of fasteners, along with other tools or supplies to ensure you have all you need to tackle the job, especially if you're taking on a DIY project for the first time.
Plus, when you shop at Zoro, you'll always enjoy competitive prices on tons of great brands you know and trust. We make the shopping experience as fast and seamless as possible with free shipping on orders over $50 for registered users, Net 30 payment terms for qualifying customers, and an unparalleled customer service experience.

Related Categories

Hex NutsLock NutsSpring Nuts & Cage NutsCoupling NutsHex Head Cap Screws
General WashersSocket Head Cap ScrewsCotter PinsFully-Threaded Rods & StudsSpring Pins
castle nutcastle nut castle nut5/8-18 nut5/8-18 nutscastle nut wrench
slotted hex nut3/4-10 nuts3/4-16 nutsmetric castle nuts5/8-11 nuts

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