When it comes to letting your engine and valve covers breathe, Spectre has you covered in style. Spectre offers two different twist-in breather styles, one with a squared off dome and one with a rounded dome. Both come with a chrome finish. These breathers are designed to replace the twist in oil filter cap and give you a breather filter at the same time. These products are legal in California only for racing vehicles which may never be used, registered, or licensed for use upon a highway. See spectreperformance.com for CARB status on each part for a specific vehicle.