This is a patented product. The cup head adopts a twist-lock switch, which completely prevents water leakage—achieving 100% leak-proof performance. With a large water flow rate and extremely simple operation, it allows pets to drink happily and freely. The cup body is equipped with two foldable water bladders with capacities of 1000ml and 1500ml respectively, which is the largest capacity configuration on the market. When not storing water, the bladders can be folded for storage, resulting in a small volume and light weight. Additionally, a special storage bag is included, which facilitates carrying when the bladders are filled with water and also protects the bladders from damage. Designed specifically as a drinking water solution for large dogs during travel, this product can meet the outdoor drinking needs of any large dog or multiple dogs. It is an essential outdoor pet supply.