This is a tool for Oil and Production water truck drivers. It allows you to enter the top and bottom gauges of a 400/bbl battery tank and then it converts that into the amount of barrels and gallons of oil or water that you have in your trailer.
Hope this helps some of you:
Let me know if there is a feature you would like to see. Also if you use battery tanks other then 400/bbl battery tanks, let me know the math and I might add it.