This Type X panel consist of an abuse defiant core encased in heavy abrasion, mold and moisture resistant blue face paper and brown back paper manufactured from 100% recycled paper. At an independent laboratory accredited in accordance with ISO 17025-2005, M-Bloc panels have been tested to the industry's most rigorous standard achieving the best possible results per ASTM D3273, scoring a perfect 10 thus minimizing the risk of mold and mildew growth.