- Thread Class
- 3A
- Thread Direction
- Right-hand
- Thread Length
- 0.418 inches minimum and 0.438 inches maximum
- Fastener Length
- 1.173 inches minimum and 1.183 inches maximum
- Head Style
- Flat chamfer
- Head Diameter
- 0.419 inches minimum and 0.437 inches maximum
- Head Height
- 0.209 inches minimum and 0.219 inches maximum
- Shoulder Diameter
- 0.3085 inches minimum first shoulder and 0.3105 inches maximum first shoulder
- Shoulder Length
- 0.745 inches minimum first shoulder and 0.755 inches maximum first shoulder
- Internal Drive Style
- Hexagon
- Nominal Thread Diameter
- 0.250 inches
- Width Across Flats
- 0.156 inches nominal
- Thread Quantity per Inch
- 20
- Minimum Tensile Strength
- 160000 pounds per square inch
- Hardness Rating
- 32.0 rockwell C minimum overall and 43.0 rockwell C maximum overall
- Shoulder Shape
- Round first shoulder
- Material
- Steel comp 4037 overall or steel comp 4137 overall or steel comp 4140 overall or steel comp 8630 overall or steel comp 8740 overall
- Surface Treatment
- Cadmium overall and chromate overall
- Surface Treatment Document and Classification
- QQ-P-416, ty 2, cl 3 fed spec single treatment response overall
- Thread Series Designator
- UNC
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.