Comments about Westcott� Data Processing Magnifying Ruler, Clear, 12":
This ruler has four different scales of measurement, each extremely useful for different purposes. In addition to the usual inches divided into 16ths of an inch, there's an inch of 32nds; millimeters; and 10-pitch and 12-pitch type measurements, which actually is equal to tenths and sixths of an inch. It's transparent, so you can see what you're measuring. I had one that I lost 15 years ago and have been looking for another one ever since.