This Velleman K6502 Thermostat Electronics Soldering Kit offers a unique feature for temperature control. In addition to functioning like any other thermostat, this K6502 kit allows you to conveniently choose between day and night temperature settings using a telephone. The K6502 kit boasts a remote control facility that operates through the telephone keypad, requiring a DTMF type phone for compatibility. Experience real-time feedback as audio signals are transmitted, providing the user with a comprehensive report on the thermostat's current settings. To ensure secure switching, a user-defined security code is effortlessly entered into the telephone.