12 Screw In Breather

The Peterson Fluid 12 Screw In Breather is a precision engine ventilation component designed for high-performance and custom engine builds where crankcase pressure management is critical. This screw-in breather serves as an essential air passage control device, allowing trapped gases to exit the crankcase while preventing oil mist and contaminants from entering the engine. Built for serious enthusiasts and professional technicians, the 12 Screw In Breather integrates seamlessly into engine blocks, cylinder heads, and custom fabricated aluminum bungs to optimize breathing efficiency and engine longevity.

Constructed from black anodized aluminum, this breather delivers corrosion resistance and durability in demanding engine environments. The screw-on design allows direct installation into welded aluminum bungs or clamp-on mounting configurations, providing flexibility in custom engine bay layouts. The anodized finish protects against oxidation and heat stress, ensuring reliable performance across extended operating temperatures. Weighing just 0.68 lbs with compact dimensions of 4.7 x 4.4 x 7.2 inches, the unit maintains a low-profile footprint ideal for tight engine compartments while maintaining full functional airflow capacity for efficient crankcase evacuation.

Street rod builders, vintage car restorers, and performance engine shops rely on Peterson Fluid breathers to handle the demands of modified and turbocharged powerplants. The screw-in configuration works with both weld-on aluminum bung installations and clamp-on mounting systems, adapting to various engine block designs and custom fabrication approaches. Installation requires integration with an aluminum bung assembly—either shop-welded or pre-assembled—making this breather ideal for builders who demand precise control over crankcase ventilation routing and pressure regulation in specialty engine applications.