Structural Insulated Panel, also called SIP and Sandwich board. It consists of a sandwich of two layers of structural boards and an insulation foam in between. Panel skins are OCM board, FCB, and OSB. Insulation core can be EPS, XPS, PUR, PIR so on. Expanded Polystyrene(EPS), Extruded Polystyrene(XPS), Poly Urethane(PU), and PIR. Panel Specification Standard sizes are 4*8' 4*9' 4*10' in various thicknesses.