White 5mm Foam Board A0, A1, A2, A3, 8 x 4 Foam centred Board – graphicsdirect.co.uk
Amazon.com : 100 White Signs Board 18x12 inch x 4 mm Corrugated Plastic, Pack of 100 Pieces, Great for Advertising Any Events, Yard Sale, Open House, Estate Sale, Election Signs, Ship Same
Smart-X Printing | Kappa Board Printing Alternative | Colour Graphics