For those that like to collect old tools and rulers, this one may appeal to your interest!! It is a 12″ steel ruler put out by the Union Tool Company-Orange Mass, USA. One side has a divet that stretches the length of the ruler to be able to attach other parts (like protracter) for measuring a variety of things. The other side has measurements as small as 4/32nd of an inch. It’s a very precise way to measure for special machinist projects. The ruler has lots of wear and tear and yet the numbers are visibly present and in good working order!