Quick Fuel offers these replacement carburetor vacuum secondary diaphragms to get your carburetor working like it should. The diaphragm on a vacuum-operated secondary carburetor needs to be in good shape and free of leaks, or else it may not open at the right time, or at all, causing a serious loss in power. These Quick Fuel carburetor vacuum secondary diaphragms are perfect replacements for your old, worn-out diaphragms that could be robbing you of potential power and performance.