... 3. Waterproof and heat insulation 4. Fast and convenient installation EPS sandwich panel Specification:External steel panelThickness: 0.4mm ~ 1. ... PE/HDP/PUDF, Stainless steel with brushed/mirrored. Insulation materialType: EPS , Density: 12~25 kg/cu.m Panel Width (mm): ... of powder-coated steel sheets. And insulation materials usually use EPS, XPS, PU, Rock wool, Paper honeycomb, Aluminum honeycomb etc ...