This replacement Dry Box Assembly, from Philips Respironics, helps prevent internal water damage on all DreamStation CPAP & BiPAP. The Dry Box Assembly fits on the interior of the DreamStation creating a protective, barrier between the water chamber and the rest of the sleep therapy, capturing and retaining water spills, seepage and leaks so that they do not damage your CPAP or BiPAP. The Dry Box Assembly must be in place at all times while is in use. CLEANING & CARE: The DreamStation Dry Box Assembly may be removed and cleaned as necessary when the seal becomes loose or dirty. For best results, clean by hand with warm water and mild soap. Once clean the assembly should be laid flat to dry completely, out of direct sunlight and/or heat, before reinstallation.