Cork cells contain a waxy, rubbery substance called Suberin which strongly repels water. Because of Suberin, water cannot penetrate into the cells of cork bark, making cork products water-resistant, and preventing the growth of mold, mildew, and moisture. This also gives cork anti-allergenic properties.

Cork is the outer bark of the Cork Oak tree. It is stripped from the tree from May to August by skilled harvesters, and the tree is not harmed in any way, forming new protective layers of cork quickly after its bark is removed. Stripping the cork bark is actually beneficial to the health of the tree.

The roots of the cork oak create watersheds and absorb nutrients, preventing soil erosion. The acorns that grow on cork oaks provide food for countless endangered animal species. Cork forests are among the most important ecosystems in the world, second only to the Amazon rainforest.