SYN001 Synchrometer Weber Jets / Chokes & Components Carburettor Synchrometer (SK) These are for synchronizing all multi-barrel or multi-carburetor automotive applications. This handy device measures the exact amount of air flowing through the carburetor, making the idle speed and mixture adjustments much more precise. The SK Synchrometer fits airhorns from 1 5/8\' (39mm) to 2 1/8\' (55mm) in diameter, including the 40, 42, 45, and 48mm sidedraft (DCOE) and downdraft (IDF) carburetors. It can fit other carburetors using the adapters available below. The STE SK Synchrometer measures flow mass from 1-30 Kg/Hour.