It is a power off delay disconnect module suitable for cooling fan, exhaust fan delay.Turn on the output when there is a signal, and turn off the output after the signal disappears. This is a high-precision timer relay module with stable and reliable performance.It has fine workmanship, good performance and a long service life. First select the overrun time range 0-30 seconds, 0-300 seconds, 0-30 minutes or 0-300 minutes with the red switches. Then adjust the time within the chosen range with the blue rheostat. Time Range:First Gear: range 0.2-30 seconds, accuracy: 0.1 seconds; Second Gear: range 0.2-300 seconds , accuracy: 0.3 seconds; Third Gear: range 0.2-30 minutes, accuracy: 1.8 seconds; Fourth Gears: range 0.2-300 minutes, accuracy: 18 seconds. .