12" woofer used in MR series and 4652, 500w, 8 ohm
http://www.jblpro.com/pub/technote/jblpro_alpha.pdf
from what i can see, it appears as if it isn't made for car audio.
http://www.jblpro.com/pub/technote/jblpro_alpha.pdf
from what i can see, it appears as if it isn't made for car audio.