This is a replacement water chamber that is used with the Philips Respironics DreamStation CPAP and BiPAP Heated Humidifiers. The water chamber can be cleaned in the dishwasher on the top rack at least once a week or hand washed daily with mild detergent. Once clean it should be allowed to dry out completely, out of direct sunlight and/or heat, before reinstalling in your sleep therapy device. Replacing the water chamber is necessary whenever the chamber appears worn or damaged.