For the first time, the D'Addario Two-Way Humidification System (formerly Humidipak) is now available in bulk 12 packs. This is the perfect solution for luthiers and guitar repair shops. The Two-Way Humidification System is the first maintenance free, humidity control system, made by Boveda, which preserves a constant 45%-50% relative humidity level within your instrument's case. This eliminates all maintenance and guesswork.

Features: Two-Way Humidification bulk 12 pack replacement packets Automatic humidity control protects your instrument against warping, cracks, and other damage cause by lack of humidification Eliminates the guesswork and anxiety of maintaining your instrument’s proper humidity level