Wow! This timer is great. It almost will run your whole growing area. For example, It can run an exhaust fan, then run a co2 system, then feed plants, then wait for a while and then, do it all over again for as long as you want! It can time equipment down to 6 seconds of ON time and as little as 1 minute of OFF time. The equipment is timed from station 1 through station 4. Around and around it times. If you don't want equipment to operate in the night, simply plug that stations power cord into an external timer with your custom time for that station. Not for timing lighting systems. I could have used this timer about twenty years ago. Why did it take so long. A darn good buy at twice the price!