D'Addario Humidipak Automatic Humidity Control System for Acoustic Guitar.
The Planetwaves Two-way Humidification System from D'Addario brings you Boveda's patented, automatic, two-way humidity control technology. This humidification system releases or absorbs purified water vapour to maintain a constant 45%-50% RH within a sealed environment (your guitar case) - the ideal climate for wooden instruments. Simply place the humidification packets with the included pouches into your instrument case as instructed, close the lid, and that's it! Kit includes: 1 Headstock pouch, 1 Double-sealed soundhole pouch, 3 Boveda packets, 1 instruction sheet.