420A's in large frames.
The only large framed 420's i've encountered in the past were 420-8B's or C's with the new style stepped alnico motor of the 416-8B.
Matched Pair Altec 420A Speakers fom Santana 879A Cabs - eBay (item 190401898546 end time Jun-08-10 18:03:54 PDT)
