SD module?

[C-Martin]

was browsing eBay and i found this...

http://cgi.ebay.com/Rare-Seymour-Du...yZ121161QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


what is it?

 

[the guy who invented fire]

Re: SD module?

it's a module for a SD Convertible amp from the 80's