Protect-A-Bed Bed Bug Proof Box Spring Encasement - California King will provide your bed a superior protection against bed bugs. This guarantees to fully encase the box spring and it is tested and proven to be bed bug entry and escape proof. It features a unique patented BugLock with Secure Seal which is specially created to prevent the zipper from opening and allowing bed bugs to enter. It’s also effective against dust mites, allergens, dirt and liquids. You can now sleep soundly at night knowing that you have the best defense against infestation. It is also the leading choice among hotel industries. This product is machine washable and it is designed for the California King Size bed. It comes with a single cover for box spring.