About this product PSE certified With a large 4L tank and top-fill function, it's easy to use for long periods without hassle. In addition to UV sterilization and high-temperature sterilization, the negative ion function keeps the air clean. You can comfortably adjust various functions with remote control operation. An automatic shut-off function works when the water runs out, ensuring safety. With a quiet design and energy-saving performance, it is ideal for use in offices and homes.