The XL ExHale CO2 Bag is for medium to large grow spaces. The XL will provide a 6x6 foot or 288 cubic foot space with CO2 for 6 months guaranteed. The XL ExHale comes with a freshness seal that doubles as a hanger. Steady supply of CO2 for 6 months guaranteed Maintenance free No heat No electricity Patent pending genetics Suitable for Organic Production Made in the USA How to Use ExHale ExHale comes complete, simply follow the instructions and place the ExHale bag in your grow space and leave it alone to do its job. A continuous shower of CO2 directly onto your plants is the most efficient way to deliver CO2. Placing the ExHale CO2 Bag slightly above the level of your plants will ensure they receive the CO2 they need 24 hours a day for up to 6 months. ExHale can be used for both vegetative plant growth as well as for fruit and flower production. If you have a ventilation system, place the ExHale bag in close proximity to the fresh air intake. CO2 will be drawn upwards through the canopy.