Strong polypropylene mats are perfect for containing mess and keeping your space neat. Conveniently marked with a grid for easy measurements and alignment, the translucent mats are flexible, waterproof, and resistant to glues and stains. They can even be used on overhead projectors. Use them, wash them off, and use them again! 19-5/8" × 14-1/8" Measuring grid in 3/4" (2cm) squares.