Internal combustion engines use a mixture of air and petrol to generate their power. The performance therefore is influenced by the air flowing into it and the petrol that is metered out by the carburettor. Unless the air flow in Twin or Multiple carburettors is correctly set, the correct mixture adjustment is unlikely to be achieved. Suitable for use on SU, Solex, Auto-Lite (Formoco) Stromberg, Weber and Zenith and can be adjusted to fit most carburettors including side-draught, down-draught with air intakes (Venurei) from 25mm to 67mm (1”-2”) diameter
