Moroso #22630 Vacuum Relief Valve, Billet Aluminum, Natural, -12 AN Male O-Ring, Each.
Vacuum relief point is adjustable by turning the built-In adjustment knob to get the precise amount of vacuum desired. Tightening the integral locknut keeps the adjustment locked until the next adjustment is needed.
Can be disassembled for easy cleaning and maintenance and will work with any vacuum level
They are made of 6061 aluminum and have a smooth, attractive finish