Intelligent watering computer: The watering duration varies from 1 second to 99 minutes and the frequency from 1 hour to 15 days. 3 Separate Irrigation Systems: Setting up the 3 independent irrigation schedules can save your watering plan, Each irrigation schedule can set different watering frequency and watering time, allowing youto adjust the watering time more flexibly and better meet your needs. Automatic rain sensor: The top of the smart timer is equipped with a rain sensor chip. When the chip comes in contact with rain, it will automatically delay watering until there is no more water on the chip. Manual irrigation and child lock: The manual button allows instant and flexible watering without interrupting your set watering schedule. Child Lock can lock the timer can avoid accidentally changing the programmed setting. Special attention: lithium batteries are prohibited. Two 1.5 V alkaline batteries must be used.