the TNB CO2 Refill Pack gives growers the ability to reuse their existing Enhancer bottles so they can save money and reduce their environmental footprint at the same time. Simply empty the contents of the original bottle, give it a quick rinse and add the contents of the refill pack. CO2 instantly becomes available for use once again. Boosting plant production and improving overall health, CO2 is an essential element of photosynthesis. The TNB CO2 Refill Pack consists of the same great recipe as The Enhancer, providing convenience and an amazing option for growers looking to supplement their gardens with passive CO2. With The Enhancer known for delivering levels of CO2 comparable to a propane or natural gas burner, many growers will be turning in their tanks and opting for this CO2 with this safer, all-natural method of CO2 supplementation.