Our packs are the appropriate size for smaller enclosed spaces, like small pill jars and baggies. The 4 gram size is not big enough for full size wood humidors, use our 67g packs for humidors. Boveda is scientifically engineered to maintain a precise relative humidity in an enclosed space.
Each Boveda consists of a specially prepared saturated solution of pure water and natural salt. This saturated solution is contained within a water-vapor permeable "reverse osmosis" membrane. Within an enclosed container, Boveda maintains a predetermined level of (RH) by releasing or absorbing purified water-vapor as needed through the membrane.
Boveda provides the cleanest and most purified humidity of all other products available on the market today.