Thank you very much for viewing. This is a pet bottle water dispenser set that automatically replenishes water as it is used. A pet bottle becomes the tank. 【How to set up the pet bottle】 1. Screw a pet bottle filled with water into the center hole of the main unit. 2. Once the pet bottle is set, water will be supplied naturally. ※ Depending on the diameter of the pet bottle's mouth, it may not fit. ※ Remove the entire cap from the pet bottle before setting it on the main unit. 【Quality Indication】 Material: Polypropylene Size: (approx.) Width 22.5 x Depth 22.5 x Height 5cm, Inner diameter 20cm, Center hole diameter 3cm New, unused. No original box due to home storage. Please consider the product photos and feel free to ask any questions in the comments. Please note that we cannot accept cancellations, returns, or changes after the item has been shipped to prevent any trouble. We will wrap it with simple bubble wrap and ship it via宅配便 (courier service). Note: Pet bottles are not included. You will need to prepare your own. Thank you for your understanding. We look forward to your consideration! B28