Made of high-quality materials, it is sturdy. Double fixing, can be installed on one side or at right angle. Suitable for most aquariums with different wall thickness, with water level adjustment function. Small size, easy to store and carry, no drilling required, easy installation. There is an internal interface that can be connected to the trachea exhaust, which is silent. Product use: Fresh water fish tank replenishment controller Colour: As Shown Material: Plastic A: With adapter, for coke-bottle Package Contents: 1 x Water Level Controller Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.