AN4 Bolts -- Undrilled Head
AN4 bolts have a 1/4-28 UNF thread and a 1/4" diameter shank. The 0.469 inch thread length on all AN4 bolts (except AN4-3A, which has 0.406 inch thread length) is designed to accommodate a full-height nut and an AN960-416 washer.
A or no A? AN bolts were originally designed to be used with a castle nut and cotter pin, so the base part number indicates a drilled shank. The addition of an "A" at the end (for example, AN4-13A) indicates an undrilled head and an undrilled shank for use with a self-locking nut.
AN bolt nomenclature can be confusing. Please take a look at our page on Identifying AN Bolt Sizes.
Related Technical Documents |
Identifying AN Bolts: Sizes and NomenclaturePrintable AN Bolt Grip Length Chart - Fractions (PDF Format)Printable AN Bolt Grip Length Chart - Decimals (PDF Format) |
| Image | Part No. | Description | Price | Stock Status |
|---|---|---|---|---|
 | AN4-Size | AN4 Airframe Bolt, 1/4-28 Thread | Click to check price | Some In Stock |
 | 3319-001 | AN Bolt Identification Gauge, AN3 thru AN10 | $17.99 | In Stock |
 | 3329-001-Color | (HAO) Dykem Cross Check Torque Seal Marker, 1 oz Tube | $7.49* | In Stock |
* Quantity Pricing Available
Related Products |
Airframe (AN) Bolts |