Used for more accurate dispersal of Carbon Dioxide and especially worthwhile in larger rooms. Tape one end to your regulator and hang just above your plants canopy. Put a knot in the other end and pierce numerous holes with a pin in the tubing where you would like the CO2 to fall. As CO2 is denser than air it will drop, this ensures maximum uptake by your plants and minimal extraction through your ventilation.
Sold per meter