Amazon.com: Mega Format Expanded PVC Plastic Sheets - 12" X 12" Rigid White Sheet for Crafts, Signage, & Displays - Sintra, Celtec PVC Board - Waterproof for Outdoors Use - 1/4" 6mm
PVC Foam Board Sheet,12mm x 300mm x 300mm,Double Sided,Expanded PVC Sheet - White - Overstock - 37253517