Introducing the Umbra Stream Water Fountain modern style and convenience meet relaxation! This tabletop fountain offers more than just ambiance to any home or office space; it also helps improve air quality by adding moisture to dry air. The internal MAX/MIN water line indicates how much water is needed to smoothly run the Stream Water Fountain. Keeping water within these lines controls the level of sound creating the gentle, soothing trickle of water. The Stream has plenty of room for 3.5" planters or stationaries, so you can add elements to this piece that will complement your dcor perfectly. Since it's powered by a simple USB plug, you won't have to worry about cords and can easily control it with the on/off switch on the cord. Will run for 50 hours between refills at max water line. Measures 12.5 x 4.5 x 5.38" (32 x 11 x 14 cm). Do not place on surfaces or tabletops that have potential to be water damaged. The Stream Water Fountain is composed of recycled plastic with a recycled mixed wood fiber, adding a natural texture to the surface. This material is easy to clean, rust free and long lasting. For consistent water flow, we recommend allowing the water to run for a few days. If you are hearing the motor, ensure you are keeping water within the min-max line. If motor starts grinding, STREAM needs to be topped up with more water.