This is the best, tempered hardboard available. This Masonite bat is 1/4" thick, with a tempered surface delivering water-resistant performance. Slightly absorbent and smooth on both sides. The 12" bat is the workhorse of all production potters -- with the proper care, a stack of these bats can last you a long time.
Instructions for care: Do not submerge or saturate in water, this will cause them to warp and delaminate. Wipe clean with water-soaked sponge and dry with a towel. Lay it flat to dry.