Improve your yield with The Kronus 4® - Day/Night Temperature Controller with Night Outlet. This product controls temperature and CO2 in your grow area at your preferred settings. The 'CO2 ON' feature is only activated during daylight periods to dose CO2 when your plants are able to uptake it, and is disabled during the nighttime hours or when the temperature exceeds your preferred settings. The built in ten (10) minute 'CO2 delay' feature deactivates CO2 equipment if the day temperature setting is exceeded. Features a ‘Night Only’ output to assist the gardener with the maintenance of the garden after the lights have turned off. The Kronus 3® is the ultimate in temperature controls for the expert gardener! It is easy to understand and use with highlighted ‘Grow Zones’ and comes with a 25 foot modular remote temperature sensor. 15 Amps/120 Volts/60 Hz. 3 year warranty.