Got the product, plugged it into my car, everything worked.  Good news so far.  The second time I used it, the USB ports didn't work.  Maybe I blew a fuse on it, except the 12 V sockets were working.  Just a defect in the USB ports.  I got a refund, so the seller was great about it.  And I know manufacturing is never 100% perfect, but I wasn't willing to try again.  Bought something else.