The Injen RD series is a cold air intake system for the enthusiast craving mid-range power. The intake tube is strategically placed behind the front bumper to acquire colder, denser air. Although most of the RD series are a one-piece design, some are two-piece designs due to the mass air flow meters. RD system is certified or pending by the California Air Resource Board (unless otherwise noted) and backed by Injen Technology's limited lifetime warranty.