- Thread Class
- 3A
- Thread Direction
- Right-hand
- Thread Length
- 0.955-1.032 in
- Fastener Length
- 1.015-1.062 in
- Head Style
- Hexagon
- Head Height
- 0.209-0.229 in
- Width Between Flats
- 0.428-0.440 in
- Hole Diameter
- 0.070 in nominal
- Nominal Thread Diameter
- 0.250 in (1/4-28 UNF)
- Grip Length
- 0.030-0.060 in
- Hole Quantity
- 6
- Hole Type
- Drilled
- Features
- Finished head
- Threads per Inch
- 28
- Min Tensile Strength
- 160,000 psi
- Hardness
- 36-40 HRC
- Hole Config
- Hexagon longitudinal hole
- Material
- Steel (4140/8740/8630/8735/4130/4037)
- Material Specs
- MIL-S-5626, MIL-S-6049, MIL-S-6050, MIL-S-6098, MIL-S-6758, AMS 6300
- Surface Treatment
- Cadmium + chromate per QQ-P-416 Type 2 Class 3
- Thread Series
- UNF
- Specification
- NAS564
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.