One side of this 12" ruler is calibrated in sixteenths and tenths of an inch; the other side, in centimeters and millimeters.
I ordered a second one of these rulers because they are great. The material is good quality and yet the edge is not too thick. I especially like that one side of inches is divided into tenths. You just can't find that much at all. It's been a very useful ruler for our family.