D'Addario Humidipak Automatic Humidity Control System (For Guitar) Passive Humigel crystals are very hygroscopic

Humigel crystals are very hygroscopic and hold up to 400 times their weight in water

wide-range frequency response for exceptionally clean and natural reproduction of both music and speech

Taper: Short

Switching 5-Position Blade: Position 1

D'Addario Humidipak Automatic Humidity Control System (For Guitar) Passive Humigel crystals are very hygroscopicThe first two way humidity control that maintains a constant 45% 50% relative humidity level within your instruments case Protects your instrument against warping, cracks and other damage cause by lack of humidification No more manual adjustments based on seasonal changes, geographic locations, temperature, or other factors Unlike refillable humidifiers Eliminates the guesswork and anxiety of maintaining your instrument's proper humidity level.