Built-in solar panel charges the included 1200mAh Ni-MH battery. Enjoy over a year of worry-free operation! Low battery? Simply place in sunlight for 1-2 days Built tough for harsh outdoor conditions (-20°C to +70°C). Dust-tight and protected against water jets Built-in eco-friendly nickel-metal hydride battery, ultra-low power consumption Solar charging, built-in battery powers the device when there is no sunlight (The product printed words may vary depending on the batch, but this does not affect use) Color: As Shown Material: plastic Package Contents: 1*Solar Rain Sensor 1*Gateway Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.