We have a new package of Stenso 3" letters & numbers (126 letters numbers and 54 Misc signs). They are black and are supposed to permanently stick and be able to use on all surfaces. I believe these date to the 1970's or so, I cannot guarentee the sticky backing is still good. They were put out by Dennison. Upon initial posting I have a few of these. I did notice (shown in photo's) that it appears as though the letters have "shrunk" a tad.