The MS20426AD3-8 is a 100° countersunk (flush head) solid aircraft rivet made from 2117-T4 aluminum alloy (AD series), designed for structural aircraft sheet metal assemblies where a smooth aerodynamic surface is required.

The “3” indicates a 3/32" diameter, while the “-8” dash number corresponds to a 1/2" length, making it suitable for thin aluminum skins and light structural stacks where a flush finish is needed after installation. It is part of the standard MS20426 / AN426-style aviation rivet family used across certified aircraft construction and repair.

This rivet is installed using a pneumatic rivet gun and bucking bar, with the head seated into a 100° countersunk hole. The shank is then formed on the opposite side into a shop head, creating a permanent structural joint used in aircraft skins, ribs, access panels, and fairings.

The 2117-T4 (AD) alloy provides typical shear strength around 26,000 PSI, along with good fatigue resistance and corrosion protection due to its self-aging heat-treated properties, making it a standard choice in general aviation structures.

Key features include:

MS20426 100° flush head solid aircraft rivet
Size: 3/32" diameter × 1/2" length (-8 dash number)
Material: 2117-T4 aluminum alloy (AD series)
Approx. ~2600–2650 rivets per 1 lb pack
Flush (countersunk) head for aerodynamic surfaces
Requires 100° countersunk hole preparation
Installed with rivet gun + bucking bar (double-sided access required)
High shear strength (~26,000 PSI typical)
Heat-treated self-aging aluminum alloy
Corrosion-resistant coating (MIL-spec anodize/chromate)
Common in aircraft skins, fuselage panels, ribs, and fairings
Standard replacement for AN426AD3-8 in aircraft maintenance
Used where smooth airflow and clean exterior finish are required