21mm type PHBG racing carburetor in the 'black edition' The Maxtuned type PHBG carburettors have a gasoline, vacuum and oil connection. The carburettors are delivered with M5 main jets. A 92 is installed as standard. Connection widths: Air filter: 32mm Intake manifold: 25mm HD: 90 Gives your vehicle significantly more acceleration and top speed. Suitable chokes: C11637 (folding choke on carburettor)//P316.0010 (with cable) Universally suitable for Simson, mopeds, mokicks, quads, scooters, etc. It is best to order a suitable M5 main jet set directly