Panels and panel materials are composite structures which consist of multiple layers or skins bonded to or sandwiching a core material such as multilayer sheets, cored laminates or industrial structural panels. They are made from a variety of metal, plastic, wood and composite materials. Panels and panel materials carry product specifications such as height, density, compressive strength, tensile strength, shear strength, shear modulus, flexural strength, flexural modulus, water absorption, and R-value. Panels and panel materials are available from a variety of sources and meet standards from organizations such as the American Society for Testing Materials (ASTM).