Amazon.com : Corrugated Plastic Sheet for Indoor and Outdoor Use - 3/16 Inch Thick Poster Board, 24x36 Inches - Pack of 5 White Plastic Board Sheets - Waterproof Coroplast Sheets and Lightweight
4mm Corrugated plastic sheets: 24 X 36 :10 Pack 100% Virgin White
Amazon.com : Corrugated Plastic Sheet for Indoor and Outdoor Use - 3/16 Inch Thick Poster Board, 24x36 Inches - Pack of 2 Black Plastic Board Sheets - Waterproof Coroplast Sheets and Lightweight
48" x 96" 6mm SHEETS
PLASKOLITE 0.157-in T x 48-in W x 96-in L White Corrugated Plastic Sheet in the Polycarbonate & Acrylic Sheets department at Lowes.com