The Resmed H5i Water Tub can be disassembled effortlessly and placed in a dishwasher to clean. The ResMed H5i Cleanable Water Tub works well with the both the S9 Series and the H5i series. The Resmed H5i Water Tub can be easily taken apart (and reassembled) for cleaning. The ResMed H5i cleanable Water Tub serves as a replacement tub for the normal H5i Heated Humidifier Water Chamber. Water chamber capacity is 380ml.