This 20-meter long 7mm thick foil foam thermal insulation liner is an essential upgrade material for camper van and motorhome conversion. Featuring high-density closed-cell foam with reflective aluminium foil layer, it integrates heat insulation, cold preservation, sound deadening, vibration damping, waterproof and moisture-proof functions in one sheet. Effectively stabilize vehicle interior temperature, reduce driving noise and prevent metal rust & mould growth, ideal for DIY camper conversion projects. Core Specifications Total Length: 20 Meters Thickness: 7mm Surface: Heat Reflective Aluminium Foil Base Material: High Density Closed-Cell Polyethylene Foam Features: Thermal Insulation, Sound Deadening, Waterproof, Anti-Condensation, Vibration Dampening.