Fastener Length

0.388 inches maximum

Head Style

Flush (flat) countersunk

Shank Diameter

0.155 inches minimum and 0.159 inches maximum

Shank Style

Self-plugging mechanically locked stem

Head Major Diameter

0.282 inches minimum and 0.290 inches maximum

Expansion Device

Serrated stem-type W

Grip Length

0.188 inches minimum and 0.250 inches maximum

Countersink Angle

99.0 degrees minimum and 101.0 degrees maximum

Material

Aluminum alloy 2024 stem

Material

Aluminum alloy 5056 locking ring & sleeve

Surface Treatment

Anodize stem or chromate stem

Surface Treatment Document and Classification

MIL-A-8625 mil spec 1ST treatment response stem or MIL-C-5541 mil spec 2ND treatment response stem

Specification/Standard Data

80205-NAS1921 professional/industrial association standard