1. Tips: When installing the trachea, note that it is not divided into left or right, but one side should be longer and the other shorter. The shorter side corresponds to the water level. The maximum water level can be adjusted by modifying the length of the trachea based on usage requirements. 2. Quality Material: The refill is made of ABS plastic, offering corrosion resistance and a long service life. The noise reduction device effectively minimizes water resonance noise. 3. Automatic Water Refill: Water from the bottle flows automatically into the aquarium or turtle tank to prevent water shortage, with replenishment stopping at the set limit. The water level can be adjusted by modifying the length of the outlet pipe according to actual needs. 4. Compatibility: The water level regulator features a tank wall insert/card slot design, suitable for tank wall thicknesses of 3 mm–10 mm. Specifications include 3–4 mm/5–6 mm/8 mm options. It is compatible with standard international bottle threads, such as those for 0.5–1.5L (16.9–50.7 FL/Oz) plastic water bottles.