Humidifier Automatic humidity control system for acoustic guitars, Automatically maintains the optimum relative humidity of 45-50% in your instrument case by absorbing moisture when needed Note: The packs last between...

Planet Waves PW-HPK-01 Humidipak - automatic humidity control, 45% RH. Includes headstock pouch, soundhole pouch, gives 2-4 months of use after opening, depending on temperature and air humidity (see instructions),...

"Taylor Guitar Humidifier, fits into the soundhole, ensures the perfect humidity for your guitar, the Oasis unit contains Humigel water-absorbing crystals, which capture up to 500 times their weight in water and trap..."