- Thread Class
- 3A
- Thread Direction
- Right-hand
- Thread Length
- 0.378-0.428 in
- Fastener Length
- 0.700-0.730 in
- Head Style
- Flat countersunk
- Head Diameter
- 0.464-0.507 in
- Grip Diameter
- 0.2490-0.2495 in (close tolerance)
- Internal Drive
- Offset cruciform (torque set), ribbed
- Nominal Thread Diameter
- 0.250 in (1/4-28 UNJF)
- Grip Length
- 0.302-0.322 in
- Threads per Inch
- 28
- Min Tensile Strength
- 160,000 psi
- Countersink Angle
- 100 degrees
- Surface Finish
- 32.0 microinches (grip, threads)
- Material
- Titanium alloy UNS R54520 per NAS621
- Thread Series
- UNJF
- Spec
- NAS1580
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.