Foam Board Pre-Cut for artwork and crafting – 305 Advertising Co
Amazon.com : Union Premium Foam Board 18 x 24 x 3/16" 10-Pack : Matte Finish High-Density Professional Use, Perfect for Presentations, Signboards, Arts and Crafts, Framing, Display (White, 18x24) : Office Products
Amazon.com : Ctosree 36 Pcs White Foam Board 18 x 24 Inch Foam Poster Board Bulk 3/16 Inch Thick Foam Core Board Large Sign Board for Display School Projects Presentations Mounting Arts Crafts : Office Products
Blackcore Foam Board Pack - 18" x 24" x 3/16", Black, Pkg of 2 - Walmart.com