Part Number NO PRIMARY REF 12 304 2731 having (CAGE Code IREF0) and FSC 2805 Gasoline Reciprocating Engines, Except Aircraft; and Components in stock with ready to ship. Get an instant quote for NO PRIMARY REF 12 304 2731 Ring Piston by The Design Control Authority. Fill the form below with your desired order quantity, targeted price and the expected order-fulfilment date. Our dedicated account manager will get back to you within 15 minutes.