2.75 Pro Filler Cap & Bung - Weld-In

The 2.75 Pro Filler Cap & Bung - Weld-In from MEZIERE is a professional-grade coolant system component designed for custom cooling applications in performance vehicles and racing engines. This weld-in bung assembly provides a secure, permanent mounting solution for radiator caps and overflow management, making it essential for builders who demand reliability under extreme thermal conditions.

The kit combines a durable aluminum bung with a threaded aluminum cap, ensuring both functionality and a clean aesthetic in engine bays. The 2.75-inch opening diameter accommodates standard Pro-style cooling caps, while the weld-in construction ensures permanent, leak-free integration into custom radiator tanks and overflow reservoirs. Aluminum construction throughout provides excellent corrosion resistance and thermal stability, critical factors in high-performance cooling systems.

Engine builders, fabricators, and performance shops benefit most from this professional-grade filler cap kit when constructing custom cooling systems, prototype engines, or restoration projects requiring precision coolant management. Installation requires welding equipment and metallurgical expertise; the bung is designed for TIG or MIG welding into aluminum.