The Original no-drill, no-hassle power valve blowout protection for Holley, and similar 2V & 4V carburetors since 1989. 100% made in the USA.
(Fits all carb models with vacuum source hole thru baseplate and routed into power valve chamber.)
NO drilling or carburetor disassembly required.
(Note): Some 4V models (usually double pumpers) use a secondary metering block with a 2nd power valve. Check before ordering.
U.S. Patent # 4,933,116