I will soon have a Black Shadow speaker up for sale, as soon as I swap it out for my JBL. Im putting out a feeler for the moment. It's a 12" ceramic magnet speaker made for Mesa Boogie, by Celestion. It's rated at 90 watts, and is a great sounding speaker, no issues with it. It's been in my Mark I for awhile. Im asking $60 plus shipping. If anyone here is interested. Please reply or PM me, thank you!