... polyurethane (PU), metal sheet. 3.2 Density of PU: 38~40 kg/m3, 40~42kg/m3, 42~45kg/m3 for choice, 3 ... steel sheet or mixed together for choice. 3.4 Thickness of panel: 75mm, 100mm, 110mm, 150mm and 200mm for ... and fruit. AIR COOLER *Apply to all kinds of freezer,cold storage and ice library.*IP44 protection level.* ... for dofrosting.*Built-in thermal protection.*Temperature range of -40~40 degrees.