Product review (1 stars): effective for about 2 minutes
I purchased one of these, wanting the convenience of plugging the unit into the car cigar lighter receptacle so that I could follow up after an exterior-only car wash.  However, it worked for only 2 minutes.  It continued to run but wouldn't pick up anything.  I tried it and retried it, finding that although the motor continued to run, it did not create a vacuum.  Didn't want to go to the trouble  of sending it back for repairs or replacement so I just ordered an Oreck which, I hope, will be more reliable.