Cover-Diaphragm Housing, Cover-Diaphragm Housing; 1 x 4 bbl; w/o Balance Tube;, Quick Change Cover-Diaphragm Housing, Expedites Changing Of Vacuum Spring, Allows You To Change The Secondary Diaphragm Spring Without Disturbing The Diaphragm, Carburetor Diaphragm, Carburetor Accelerator Pump Diaphragm