As wood is a natural material, no two pieces are exactly alike. Each piece has its own characteristics and personality and reacts differently to climate change. When any wood product is exposed to the elements, it develops "wood checks". A check is the radial separation of the wood fibers running with the grain of the wood. These are caused by varying temperature and moisture conditions. A check is not cracked - it does not affect the strength or durability of the part and is not covered under warranty.