Hello Guys, My sub box doesn't move at all. Basically I have 2 boxes between my rear suspension turrets. A 12" Kicker CVR boxed on the r/h side and a custom made MDF open box which I constructed and carpeted to match the sub box, on the l/h side with my 2 Kicker Amps, Crossovers and Power Distribution Block. As both boxes are designed so they are a tight fit between the rear suspension, there is no sideways or rear motion at all even under extreme cornering! There will pictures available soon on my vehicle profile showing my install. Hope this helps ............

 

Actually, in response to the "How much Velcro" question, not that much. I usually get the pre-cut strips in the package... something like 4-5" long. One on each side of the box, my 50+ pound sub in it's custom made enclosure doesn't move at all. (about 75-80 lbs total.)