- Thread Class
- 3A
- Thread Direction
- Right-hand
- Thread Length
- 0.443 inches minimum and 0.510 inches maximum
- Fastener Length
- 1.015 inches minimum and 1.062 inches maximum
- Head Style
- Flat countersunk
- Head Diameter
- 0.497 inches minimum and 0.507 inches maximum
- Grip Diameter
- 0.2483 inches minimum and 0.2492 inches maximum
- Shank Unthreaded Hole Diameter
- 0.076 inches nominal first hole
- Internal Drive Style
- Hexagon
- Nominal Thread Diameter
- 0.250 inches
- Grip Length
- 0.552 inches minimum and 0.572 inches maximum
- Width Across Flats
- 0.157 inches minimum and 0.159 inches maximum
- Thread Quantity per Inch
- 28
- Minimum Tensile Strength
- 160000 pounds per square inch
- Hardness Rating
- 36.0 rockwell C minimum overall and 40.0 rockwell C maximum overall
- Countersink Angle
- 99.0 degrees minimum and 101.0 degrees maximum
- Distance from Head Largest Bearing Surface to Shank Hole Center
- 0.864 inches minimum first hole and 0.884 inches maximum first hole
- Surface Finish
- 32.0 microinches grip
- Material
- Steel comp 4140 overall or steel comp E4340 overall or steel comp 6150 overall or steel comp 8735 overall or steel comp 8740 overall
- Material Document and Classification
- MIL-S-5626 mil spec 1ST material response overall or MIL-S-5000 mil spec 2ND material response overall or MIL-S-8503 mil spec 3RD material response overall or MIL-S-6098 mil spec 4TH material response overall or MIL-S-6049 mil spec 5TH material response overall
- Surface Treatment
- Cadmium overall and chromate overall
- Surface Treatment Document and Classification
- QQ-P-416, ty 2, cl 3 fed spec all treatment responses overall
- Thread Series Designator
- UNF
- Specification/Standard Data
- 80205-NAS334 professional/industrial association standard
Catalogue data is compiled from public DLA/FLIS sources and is provided for
identification. Availability, condition and certification are confirmed on
quotation. OmniSynk Distribution Services is a stocking distributor.