| This tiny little air filter is used inside the air cleaner to filter the air that is coming through the hose from the valve cover. It is used on all stock 4 cylinder air cleaners from 73-81. We're checking other applications before and after those dates. It should be changed every 30K miles. We have most tune up parts in stock for most 4 cylinder Datsuns in the 70's and early 80's. | 
