D'Addario PW-HPK-04 HUMIDIPAK ABSORB Automatic Humidity conditioning System

Humidipak Absorb allows you to safely return your instrument and case to the ideal humidity level. Using Boveda’s patented two-way humidity control technology, Absorb automatically soaks up excess moisture at a safe rate, to re-establish the ideal humidity level, eliminating the guesswork of revitalizing your instrument. Best of all, using Humidipak is easy. No more dripping sponges or manual adjustments. Simply place the humidification packets with the included pouches into your instrument case, close the lid and relax, knowing your instrument is safe and sound.