ISP Controllers IPS-M920WL Large Automated pH with Dual ORP Controller with Wi-Fi allows you to check in on real time chemical control activity for all your pools, spas and water features, using your smart phone or tablet. Web-based programming, monitoring, optional wifi and testing options for alert notification are built into the M920 and M920w, with optional wireless Internet access. A lockout feature is included on this model, keeping unauthorized users from making function changes. This top-of-the line automated pH, dual ORP controller is compatible with all sanitizing methods including liquid, tablets, granular and salt chlorine generators. The convenience of the unique dual ORP allows operators to install multiple output devices on the same pool. With dual ORP, you can use a primary sanitizer, such as salt chlorine generator, with a secondary sanitizer, such as liquid chlorine, for rapid response to increase bather load. The second ORP may also be used as a safety backup (second pump and tank) for liquid systems. Quick and simple to operate with push button technology, installing the M920 or M920w is a breeze, pre-assembled on a 16" x 12" mounting board (or 24" x 19" accommodates two chemical pumps), allowing you to hang it right out of the box.