... High strength 3. Waterproof and heat insulation 4. Fast and convenient install Rock Wool Sandwich Panel Specification:External steel panelThickness: ... PE/HDP/PUDF, Stainless steel with brushed/mirrored. Insulation materialType:Rock wool Density: 100-160 kg/cu.m Panel Width ... powder-coated steel sheets. And insulation materials usually use EPS, XPS, PU, Rock wool, Paper honeycomb, Aluminum honeycomb etc ...