Improper storage is the greatest constant danger to the condition of a wooden instrument. Until Boveda, humidified storage meant refilling awkward and unreliable sponges, snakes or discs. Those products only work 1-way, they add humidity whether it's needed or not, while Boveda is the world's first 2-way humidity control.
If not properly stored in a stable environment, your instrument will lose the specific geometry built into it while it was being crafted at the climate-controlled factory. This can cause warping or shrinking, which will change the tune at the least and cause damage at the most. In fact, most repair problems with wooden instruments can be avoided with properly humidified storage from Boveda.
Each Boveda consists of a specially prepared saturated solution of pure water and natural salts. This saturated solution is contained within a water-vapor permeable "reverse osmosis" membrane.