Bolts, nuts & washers
AN310 Castle Nuts
The slotted nut for drilled-shank bolts, secured with a cotter pin.
- TypeCastellated nut
Where to buy
AmericaDistributor coming soonOur partner for this region is on its way
EuropeDistributor coming soonOur partner for this region is on its way
OceaniaDistributor coming soonOur partner for this region is on its way
More distributors
AmericaMore distributors coming soon
EuropeMore distributors coming soon
OceaniaMore distributors coming soon
The thinner AN320 has half the AN310's tensile rating and is for shear-only applications, per the listing.
Pins: MS24665 cotter pins.
Specifications
| Type | Castellated nut |
|---|---|
| Materials | Cadmium-plated steel, stainless |
| Use | Drilled-shank, clevis and eye bolts, studs |
Source: a distributor's listing, checked 2026-09-30.
Sizes listed 16 rows
| Type | Part No. | Thread Size | Cotter Pin Size |
|---|---|---|---|
| Cad Plated | AN310-3 | 10-32 | AN380-2-2 |
| Cad Plated | AN310-4 | 1/4-28 | |
| Cad Plated | AN310-5 | 5/16-24 | |
| Cad Plated | AN310-6 | 3/8-24 | AN380-3-3 |
| Cad Plated | AN310-7 | 7/16-20 | |
| Cad Plated | AN310-8 | 1/2-20 | |
| Cad Plated | AN310-9 | 9/16-18 | AN380-4-4 |
| Cad Plated | AN310-10 | 5/8-18 | |
| Cad Plated | AN310-12 | 3/4-16 | AN380-4-5 |
| Cad Plated | AN310-16 | 1-14 | |
| Stainless Steel | AN310C3 | 10-32 | AN380-2-2 |
| Stainless Steel | AN310C4 | 1/4-28 | |
| Stainless Steel | AN310C5 | 5/16-24 | |
| Stainless Steel | AN310C6 | 3/8-24 | AN380-3-3 |
| Stainless Steel | AN310C7 | 7/16-20 | |
| Stainless Steel | AN310C8 | 1/2-20 |
Questions people actually ask
Where can I buy the AN310 Castle Nuts?
A distributor we checked lists it in the Americas. The link to its page, with the live price and stock, opens when the partnership does.
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