Filler Cap Polished with Bolt-In Alum Bung Small

The Filler Cap Polished with Bolt-In Alum Bung Small is a precision fluid containment component engineered for racing, automotive fabrication, and performance vehicle systems where reliable sealing and professional presentation matter equally. Manufactured by ALLSTAR PERFORMANCE, a trusted name in motorsports and high-performance applications, this small-format filler cap addresses the need for durable, corrosion-resistant caps that secure fuel tanks, coolant reservoirs, and other fluid systems without compromise. Whether you're building a competition engine bay or restoring a custom vehicle, this polished aluminum component delivers the fit, finish, and functionality that separates quality builds from amateur work.

Constructed from polished aluminum, the Filler Cap Polished with Bolt-In Alum Bung Small resists oxidation and corrosion while maintaining a professional appearance under engine bay heat and vibration. The bolt-in aluminum bung design ensures secure, permanent installation—no temporary clips or press-fit arrangements that can loosen under thermal cycling or rough handling. The polished finish not only enhances aesthetic appeal but also provides a protective oxide layer that maintains appearance across multiple seasons of use. Small-format sizing makes this cap ideal for auxiliary tanks, overflow reservoirs, and custom fabrication where space is limited and precision fit is non-negotiable.

Fabricators, engine builders, and motorsports competitors rely on ALLSTAR PERFORMANCE components for consistency and reliability in high-stakes applications. The bolt-in design eliminates the failure points associated with friction-fit caps, making installation straightforward for both shop technicians and experienced DIY builders. Weighing just 0.38 lbs and fitting compact dimensional parameters (4.9 x 1.35 x 6.8 inches), this filler cap integrates seamlessly into tight engine bays without requiring extensive repositioning of adjacent systems. Whether you're sealing a fuel cell, auxiliary coolant system, or custom fabricated reservoir, this polished aluminum component delivers OEM-grade reliability with visible quality that reflects pride in workmanship.