sealed, the box doesn't move, but i would still bolt it down if i was you. i didn't and it didn't move. it fits two 8's and has about one cubic ft of air space. this is the bottom.
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Great accomplishment only comes with great risk. I’ll accept the crippling, gut wrenching disappointment of risking all, and failing, but only by putting my whole heart and soul, my whole being into something, will I have the chance to walk among the stars.
Those who risk nothing, those who live their lives in fear, will never have that chance.
Failure is not a sin. It’s being too afraid to even try, that is a sin.