This Solar Thermometer is truely envirnomental friendly.  Different from other models found on the market, it does not need any back-up battery.  Instead, these is a built-in rechargeable battery which does not require change of battery .  Major functions include :

• Environmental friendly 2-in-1 thermometer with hygrometer.
• Solar powered with built-in rechargeable battery with long lasting operation.
• Rechargeable by indoor lighting and natural sunlight.
• Max./min. temperature memory.
• Comfort icon.
• Wall mount or tabletop.
• Temperature range: -10 to 50℃ (14℉～122℉).
• With accuracy: 0~40℃ +/-1℃, other range +/-2℃.
• Humidity range: RH 30~90%.
• With accuracy: RH 50~80% +/-5%, other range +/-8%.