4-40 STI Socket Head Cap Screw (SHCS)

Size = 4-40 x .450" STI SHCS

Head Diameter = .227"

Head Length = .140"

T10 Hexalobular Bit (Included)

PreCoil Socket Head Cap Screws are purpose-built for STI (Screw Thread Insert) tapped holes — the oversized internal threads you cut before installing a Heli-Coil.

Instead of running standard threads, only to later blow-out to STI sized, or even worse, installing Heli-coils to fixture a part, and then have to remove them before plating; PreCoil fasteners let you fixture, clamp, and assemble directly into STI-tapped holes with confidence.

Oversized external threads. Tight tolerances. No guessing.
Perfect for test fits, fixture builds, and any application where pre-insert threading can be utilized.