Posted on September 30, 2018March 4, 2022 by OwnerBuilding the custom marine fridge In this short video the building process for the custom marine fridge aboard Seadog is shown. The Isotherm 3251 ASU SP package was used as the refrigeration system. For insulation material a two-component PU foam was used, together with plywood and 4 layers of epoxy for the finishing layers.