7900 0304 ...Brand New Genuine Tannoy Diaphragm used in 623,  CMS6TDC, Definition D500, Definition D700, i8, System 6 NFM II, System 8 NFM II, System 10 NFM II, T8, V Passive Series, V Power Series. This is the diaphragm to use to replace the 7900 0485 (which is no longer available) used in the AMS8A, AMS10A.