More from Amazon.com : http://www.amazon.com/gp/product/B00J8MBRTE?tag=purrfectcatdi-20
Concrete Sliderule Volume Computer Calculator Lot of 6pcs
Calculates quantity of concrete required to fill a rectangular or round area
Calculates concrete required to fill cylinders and piers
This slide will calculate quantities up to 200 yards
Very easy to use---You are purchasing six calculators
