My buddy just got a 12 inch alpine type x and wants it in a sealed box. is there anyone that makes a sealed box big enough to fit that sub? its going into an 07 nissan sentra.

First... check the recomended enclosure volume.

If you want cheap and effective, go check out ebay.

if you want smooth and stylin, Fiberglass your own, its easy as PIE :cool:

My guess is a sub like the Type-X you're going to want somewhere from 2-3 cubic ft. I can't find the exact specs on Alpine's site but the answer to your question is yes you can find a million pre-fab boxes in that range.

Here's a couple (http://www.edesignaudio.com/edv2/index.php?cPath=38)