Sensor(s) magnetically mounts to bottom of tank(s) - Use up to 15 sensors on RV, BBQ, patio grill, etc. Tank level is updated every 5 seconds via Sonar / Ultrasoun Technology Sensor(s) communicate to bluetooth enabled mobile device, tablet or monitor in coach 3 year warranty Free downloadable app can read up to 15 sensors

 PROP 65 WARNING: This product may contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling. For more information, visit www.P65Warnings.ca.gov