... is using colour coating steel sheet as surface finishing and polyurethane (PU) as core material. This product with quick installation and good ... customer requirement,the max length is 10000mm.2.Sandwich Layer: Polyurethane(PU) Density: 38-40(kg/m3), 40-42(kg/m3), 42 ... , 100, 120, 150, 200mm.3.Fireproof:According to customer requirement. PU sandwich panel for cold storage