Hitachi's Air Bypass Valves (ABVs) is designed to accurately regulate the amount of air entering the engine when at idle (also known as an Idle Speed Control (ISC) Valve and Idle Air Control (IAC) Valve). High quality materials ensure that even under the most extreme conditions, Hitachi's ABVs will not deform or malfunction. Our ABVs are 100% air flow tested for ideal performance and are calibrated for each application ensuring your vehicle meets the strict emission standards set by the OE manufacturer which makes Hitachi's ABVs the premium choice.