Mr. Gasket Breather & Oil Filler Caps

Mr. Gasket Breather/Oil Filler Caps deliver proven crankcase ventilation performance for street, racing, and high-performance engine builds. Now part of the Holley Performance family, Mr. Gasket has been a trusted name in performance engine components since 1964—built on a legacy of race-proven quality that withstands the demands of competition and everyday driving alike.

This product line serves a dual purpose, functioning as both a crankcase breather and an oil filler cap, making them a practical and attractive upgrade for any valve cover setup. Whether replacing a worn OEM cap or dressing up a high-performance build, Mr. Gasket offers configurations to fit the job—including options compatible with race car vacuum balance systems and OEM applications.

Key Features:

• Chrome-plated steel construction for lasting durability, corrosion resistance, and a clean underhood appearance
• Internal baffle with filtration element for effective oil mist separation and reliable crankcase ventilation
• High-porosity filter element helps prevent oil blow-by while allowing the crankcase to breathe freely
• Embossed Mr. Gasket logo for a professional, finished look
• Push-on and twist-on styles available to suit a variety of valve cover configurations
• Multiple variants available to accommodate different mounting styles and engine build requirements
• Sold individually

From drag strips to street-driven muscle cars, Mr. Gasket Breather/Oil Filler Caps are a straightforward, dependable solution for crankcase ventilation management. Backed by decades of racing heritage and the engineering resources of Holley Performance, this product line is a trusted choice for builders who demand both function and appearance from every component under the hood.