Sure would of been helpful if JBL had put their logo on the diaphragms, or their part number. Not always possible of course, but on compression driver diaphragms, the plastic mounting ring sure could have something put on it. I don't have much experience with JBL compression drivers and their diaphragms, having only pairs of 2420s, 2425s, 2402s and 2405s. I think the 2402 had a number on the edge of the diaphragm, and I think my 2420s (labeled LE85) were redone, they are missing the wax seals, and I've never opened the 2425. So JBL never marked their compression driver diaphragms at all? Seems kinda odd...