The MAF 4.0 is a hot wire mass air flow sensor in a black plastic housing. It operates from a 12V supply and produces a 0-5 V output. The DC voltage is proportional to mass air flow. It is compatible with engines making up to 650 hp. It has a 4” flange inlet and 3.5” round outlet. The inlet is designed to be bolted to an air box. The outlet is designed to mate to a flexible tube and be secured with a hose clamp.