We love are isotherm, it will keep chicken frozen for weeks if it's up against the cold plate. My box has 4 to 6 in of fome and a tight seal on the lid. My isotherm uses a heat exchanger through the sink sink through hull. It use very little juice, but I'm sailing in Maine and the water temp never gets much over 62F. It also makes no noise.
Bristol 29.9 # 49