This is a rare 1970's vintage hydrulic industrial cylinder calculator/selector marked "MILLER FLUID POWER A FLICK-REEDY CORPORTION" on one side. This is a double sided slide calculator with various models and hardware on one side, and one the other side similar charts for strokes and size, mountings of other model cylinders. It is in good++ condition with very little light wear, it is very slight warped, but works fine. It measures 11.25" x 8.75", has a plastic like coating on all surfaces, the little holes you see are the 6 metal rivets that hold this three piece unit together, all in great shape.