Rico Reed Vitalizer Humidity Control - Single Refill Pack, 58% Humidity Stores reeds at ideal humidity level 58% Relative Humidity is ideal for storing, preserving, and stabilizing new or seldom-used reeds Reed tips stay flat and are less prone to warping Available in three humidity levels for various needs: 58%, 73%, and 84% Refill packs last 45 to 60 days