LevelR™ Insulation is an extruded polystyrene (XPS) foam insulation board fanfolded for easy installation over existing exterior surfaces. It is used as a rigid foam underlayment for new siding materials. It also features a crimped hinge, allowing the cladding to lie flat. The flexibility of LevelR™ Insulation aids corner-wrapping, providing sealing effectiveness and a smooth level surface for new siding.