The product is ready to use as soon as it is taken out of its plastic packaging. Place the Moshi Carbon bags wherever you want to eliminate odors and detoxify the air.  Refresh the Moshi Carbon bags at least once every 30 to 45 days for a minimum of 2 hours under direct sunlight. This procedure cleanses the Moshi Carbon bags of adsorbed toxins with UV rays, making them ready to use again. The product can be used effectively up to 2 years.