32 x 40 inch (81.3 x 101.6 cm) acid-free foamboard, 3/16ths inch (4.8 mm) thick, white board on both sides. Use this buffered pH neutral board for mounting valuable artwork that needs to be preserved indefinitely. This is a full case of 25 sheets. Save big by buying in full cases. (At this time, we only sell foam board in case quantities.) Made in USA.