iOPQO Office Stiff F^elt Sheets for Crafts, 9x12 in 3mm Thick Colored Craft Fabric Hard Pieces for Kids, Crafting, Sewing, Art Projects Hard Felt Board Blue Blue - Walmart.com
PLASKOLITE 18 in. x 24 in. Corrugated Plastic Sheet 1TW1824C - The Home Depot
Plastic Craft Sheet - Etsy
Coroplast 48 in. x 96 in. x 0.157 in. (4mm) White Corrugated Twinwall Plastic Sheet (10-Pack) WC4896-10 - The Home Depot
Amazon.com: ERRULAN Acrylic Board Clear Large, Polycarbonate Panels for Gazebo, Hard Plastic Sheets for Crafts/Photo Frame Replacement, 50/80/100/120cm Wide (Color : 4mm, Size : 1x3m/40x118 in)