R-values indicate how well the foam resists transferring heat. Denser materials have higher R-values. R-values are expressed per inch of the material; the higher the number, the better the insulating ...

This is a design for a better foam tray for the Doom Reaper Miniatures boxed sets that were sold in 2013. See here for some context. You'll need three sheets of half-inch foam, each 12x10 inch in size ...