The Filter Change Indicator from Los Angeles-based Heemang Electronics USA Co. is a programmable electronic system that displays the current condition of the filtration system. It’s a convenient way for the customer to see at all times whether their filtered water is fit to drink or if they need to change their filter. This also ensures another sale of filters at the right time. The monitor is mounted at the base of the tap with three indicator lights. When water flows through the tap, one of these lights turns on.