Check out any of the eighteen E-4 components enlisted.
Parts such as the E-4: Bolt,flange,6x25, B/brg Rad N/com, Bolt,stud,6x24, Connector.earth are included in the Nsr250r9 1990 (l) Japan Mc21-102 E-4 parts fiche.
The E-4 assembly is constructed from several parts from which the Thermo Unit Assy is the most expensive.