Venstar Comfort Call Phone Controlled Thermostat Kit Monitoring and controlling your thermostat from any phone 1-Day Programmable with up to 4 time periods Auto changeover, 2-stage heat, 1-stage cool for use with gas/electric, heat pump, electric & hydronic heat No Setup/Programming necessary for Comfort Call Thermoglow backlit electro-luminous display and backlit color coded keys and legends