Features: Name: Aquarium Water Change Valve Material: PP+ABS Purpose: Change water in the aquarium Easy to use: Suitable for inlet and outlet pipes of the filter tank with an inner diameter of 12 mm and an outer diameter of 16 mm Contents: 1 x Aquarium Water Valve Notes: 1. Item color may vary from the pictures depending on your computer's brightness and display settings. 2. Due to manual measurement, the sizes shown may vary by 1-2 cm. Function: The aquarium water change valve allows for quantitative water changes and can also be used for adding water. Premium Quality: Our hose valve is made of plastic with a special design for long-term use. Wide Use: Suitable for freshwater and saltwater aquariums; compatible with filters, pump return lines, protein skimmers, and other aquarium equipment.