Review on Munchkin True HEPA Air Filter Replacement For Air Purifier, 3 Pack by Diane Brown

i bought this for my car, based on amazon reviews. first unit didn't hold a charge (worked when plugged in only, battery is supposed to last 10hrs); amazon return/ replacement incredibly easy and replacement arrived in time for my long drive.second unit charged and it worked during a test drive, so i tossed the box and was off! unfortunately, after my 6hr drive (battery still going!), i couldnt turn it off? so yup: so cheap that this unit's button is faulty. i finally turned it off, charged it up again, used it one more time, but then multi-mode button totally useless so i am returning it as soon as the battery dies. (note: amazon customer service chat was very helpful, didnt seem to care that packaging was tossed).Munchkin is a reputable brand. i tried to call them multiple times assuming they'd help more than amazon and not wanting to trash another unit, but somehow their customer service line was never open (weird).upshot: don't waste your time or money on this model.