1. Deluxe design for control multistage AC system with a heat pump. It can control up to 2 stages cooling /3 stages heating with aux. heater.2. Easy to use and provides you with a more comfortable and convenient living environment.3. Pre-programmed for your convenience. Program a week 7 days up to four time periods and temperature set points each day to complement your lifestyle and to be applicable for many customers. 4. Programs are permanently held in non-volatile memory in the event of a power failure.5. Attractive turn-cover design, most frequently used keys are located on the LCD for quick and easy access to information. Program keys are located on the interior to eliminate accidental setting changes.6. Large LCD display with many messages for quick and easy readability and operation. Such as measurement and setting temperature, fan and compressor work status, clock and program etc.7. Automatic compressor short cycle protection extends the life of the major equipment 8. Auto or manual fan operation.9. Adjusted 1st and 2nd stage temperature differential maintains optimal customer comfort.11. Auto or manual heat/cool changeover. 12. Temperature either F or C display for added model flexibility.13. Constant hold feature allows continuous override14. Temporary temperature override15. Unique lockable function makes all keys locked to eliminate accidental operation.16. Low temperature protection 17. Infrared remote control optional producing area:China supplying capacity:10,000pcs/month