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B1821BH031C250N
Machine Screw
Description
Fastener Length: 2-1/2", Thread: 1/4-18, Thread Length: 63/64", cap screw, zinc
Specifications
| Fastener Length | 2.406 inches minimum and 2.500 inches maximum |
|---|---|
| Features Provided | Finished head |
| Hardness Rating | 32.0 rockwell c minimum and 38.0 rockwell c maximum |
| Head Height | 0.195 inches minimum and 0.211 inches maximum |
| Head Style | Hexagon Head |
| Length | 2 1/2 |
| Material | Steel |
| Material Specification | Aej429grade8 assn std 15th material response or astma354gradebd assn std single material response |
| Min. Tensile Strength (psi) | 150000 pounds per square inch |
| Surface Finish | 63.0 microinches threads |
| Surface Treatment | Zinc and chromate |
| Surface Treatment Specification | Astm b633 ty 2 sc 3 assn std single treatment response |
| Thread Class | 2a |
| Thread Diameter | 0.312 |
| Thread Direction | Right-hand |
| Thread Length | 0.875 inches minimum and 1.062 inches maximum |
| Thread Qty | 18 |
| Thread Qty Per Inch (tpi) | 18 |
| Thread Series Designator | UNC |
| Thread Size | 1/4 |
| Width Between Flats | 0.489 inches minimum and 0.500 inches maximum |
Other sizes
Parts that share this base number, ordered by size. Always verify the full specification before substituting.
- B1821BH031C088N
- B1821BH031C175N
- B1821BH031C250D
- B1821BH031C250N
Cross-reference
Similar parts
Parts with matching key dimensions — often from a different standards family. Candidates for comparison only; verify the full specification before substituting.
- MS90725-41 MS 1/4-18 · 0.086 in · Hexagon Head · Steel
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Catalog data updated 2026-07-05. Report a data error