I purchased this item new and tried it in the bathtub once, but I couldn't install it, so I'm putting it up for sale. An alarm sounds when the water level touches the sensor on the bottom of the main unit. It also has a thermometer and a time display function, which I think is convenient. I threw away the container, but the other accessories, such as the instruction manual, are included. Thank you for your interest. I hope we can do business. m(_ _)m