It was the late 70's. DnD was new and maps were meant to be blue. Back in those days photo copiers wouldn't read blue lines and so, to protect their maps, TSR made them blue. This tile set is a blast from the past and I highly recommend them to anyone who played our favorite past time during the Carter years.
The product contains 62 separate tiles on a 1 inch grid that can be easily manipulated into your favorite VTT. They'y all on the same position on the page so it's easy to crop once and affect all the tiles. What's more, because of the simplicity, auto-cropping works great! The set contains a legend you can edit and apply on the GM's layer of MapTool so a concealed door is concealed until you (the GM) says it isn't.