Opened to check the contents. Cartridge for the Shizuku humidifier. Antibacterial cartridge specifically for ultrasonic aroma humidifiers, containing 3 pieces, usable for approximately 6 months. To save on shipping costs, the box will be removed and folded for shipping. - Product Name: Antibacterial Cartridge for Ultrasonic Aroma Humidifier - Pack Quantity: 3 pieces - Model Number: ACA-002-3P - Material: Ceramic balls - Usage Period: Approximately 6 months (up to 500 liters)