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 & 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, & 48mm sidedraft (DCOE) & 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.