These are AMAZING!!!!  I have used one for about 10 years on my car.  After washing my van I dry it off with one of these and there are no water spots.  This is particularly fabulous on the windows.  I purchased more to have a 'clean' one to use on the inside of my car windows.  You do not let these dry out, if they do it is a pain to get them wet again!  THey stay moist in the container, and miraculously DO NOT mildew.  I love them.  I bought the 6 pack because of the great value, and I have gifted a couple to friends. (Yes it is a weird gift, but it was a random gift not a birthday gift....)