... the sandwich board rigid polyurethane (PU) foam high pressure, both inside and outside the metal surface layer, the option of color-coated ... steel plate, PPGI ,embossed aluminum, stainless steel plate and galvanized steel and other materials,PU cold storage is generally modular cold ... , installation time limit is short for a project, small and medium-sized refrigerator can delivery in 2-5 days, The ...