The PPM-4 is the simplest, safest and most affordable CO2 controller available today... from any manufacturer. Perfect for controlling LP or natural gas generators with PPM accuracy.

• The PPM-4 is a two-piece controller that includes a wall mounted infrared sensor with a 10 ft. cord and a plug-in pass-through controller/power supply.
• The plug in control is designed to be electrically safe.
• Designed specifically to control the carbon dioxide level in your grow environment with PPM accuracy and is easy to use out of the box due to its easy to read 3 LED interface.
• Switching set point factory set to 1450 PPM with 50 PPM hysteresis/dead-band.
• Calibration couldn't be easier. Simply step outside and press a button.
• The PPM-4 is easily mated to any 120 volt valve or CO2 Generator with a simple plug in device.