1、Adding atmospheric cavity suction is stronger, performance is better, and efficiency is higher.​ 2、A built-in porous filter prevents fish or water, sand and gravel from being sucked out. 3、With a control valve, the water flow can be adjusted to facilitate the cleaning of relatively small sand and gravel. 4、Equipped with a suction cup to secure the water pipe for easy operation. 5、​Long thickened antifreeze hose, good flexibility and durability​. Features: Adding atmospheric cavity suction is stronger, performance is better, and efficiency is higher. A built-in porous filter prevents fish or water, sand and gravel from being sucked out. With a control valve, the water flow can be adjusted to facilitate the cleaning of relatively small sand and gravel. Equipped with a suction cup to secure the water pipe for easy operation. Long thickened antifreeze hose, good flexibility and durability. Specifications: Product Material: Plastic Product Color: Gray Product Size: Total length: Approx.240cm/94.5inches Hard tube length: Approx.20cm/7.9inches Water outlet diameter: Approx.1cm/0.4inches Scope of Application: Large fish tank Product Function: Change water, absorb dirt, wash sand, keep the water quality of the fish tank clean. How to use: 1. Put the water changer into the fish tank. 2. The other end of the water pipe is placed in the bucket. 3. Open the regulating valve. 4. Gently squeeze the air chamber by hand to its automatic water. 5. Lower the suction port to absorb the fish manure and residue in the sand. Package List: 1* Water Changer 1* Suction Cup Note: When using, the water outlet must be lower than the water inlet. Because there was a manual measuring ,the size may has 1-2cm/inch difference.