Internal combustion engines use a mixture of air and fuel 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 multiple carburettors is accurately matched, correct running is unlikely to be achieved. Suitable for use on SU, Solex, Auto-Lite (Fomoco) Stromberg, Weber and Zenith carburettors and will fi t most designs including side-draught and down-draught with air intake diameters (venturis) from 25mm to 57mm (1” to 2¼”) diameter. Easy to read scale indicates the air fl ow and allows adjustment to optimum efficiency. Provides smoother and better acceleration. Supplied with straightforward instructions. Easy to read scale indicates the air flow and allows adjustment to optimum efficiency.Carbalancer can be adjusted to fit most carburettors.