The HT-02 is a professional-grade, battery-operated wired thermostat specifically designed for hydronic floor heating and gas boiler systems. Item No.: HT-02 (Battery Powered 2xAAA) Programmability: 7-day, 4-period programmable or manual/economy modes Backlight: High-contrast White LCD Backlight Material: Fire-resistant ABS+PC (IP30 Protection) Switching Rating: 0.5A for Boiler/Actuator control (Dry Contact) Temp. Accuracy: ±0.5°C with 5°C - 35°C Setpoint Range Other Functions: Child lock, Open window detection, Frost protection, Temp. calibration, Heat/Cool option Optional: OpenTherm protocol for precise digital boiler modulation (energy-saving) Certificate: CE, ROHS, UKCA, REACH Compliance Packing: Neutral White Box, OEM/ODM professional customization acceptable Product Dimensions：135 x 87 x 27.2mm

This surface-mounted thermostat has been developed to be able to switch 2-wire boiler.  which is for upgrade for your old mechanical thermostat. Item No.: HT-16 Transmitter : 2*AAA battery Programmability: 7days programmable Temperature settings: 5°C ~ 35°C, 0.5°C increments Packing : Netural White Box, OEM acceptable Cetificate:CE, ROHS, RED