BOTH THINGS WITH 2 YEARS WITHOUT USE THE AMPLIFIER WAS DIVERTED 2 SCREWS IS ONLY TO PLACE YOU OTHER NOTHING THAT PREVENTS ITS OPERATION AND THE BASS THE LAST TIME IT WAS USED WAS WORKING PERFECT EYE: IT IS SOLD JUST AS YOU ARE NOT HAVING TO PROVE THEM SO ONCE PURCHASED THERE IS NO GUARANTEE OR CLAIM OF ANYTHING REMAINS TO YOUR DECISION TO WANT TO BUY OR NOT DELIVERY AREA MALL METRO PARKINGS.