Time delay control for reliability: builtin time delay of 35 seconds when humidity is detected in a critical state. The relay will not flicker and avoids transient switching or strobing effects. Sensor quality and durable construction: uses the companys soil moisture sensor. plated contacts and widened sensing area improve conductivity, reduce soil contact corrosion, and prolong service life. Adjustable threshold for versatile control: supports a wide range of soil humidity control. set the threshold value with the potentiometer. when soil moisture is lower than the set value, the relay turns on; when moisture is higher than the set value, the relay turns off. performance relay for common loads: built with a relay capable of withstanding up to 1500W, meeting the requirements of most users. Practical use scenarios: Home garden irrigation automation: connect to a water pump or solenoid valve up to 1500W to water plants automatically when soil dries. Greenhouse soil moisture management: maintain moisture for potted plants, raised beds, or nursery trays with reliable on off control. Seedling tray and small farm applications: automate moisture regulation during propagation or early growth to support consistent conditions. Key attributes at a glance: functions include time delay and soil moisture based switching; compatible with a range of irrigation setups; corrosion resistant design with plated sensors and widened sensing area; adjustable threshold via potentiometer; robust 1500W relay for common agricultural and domestic loads.