The DAddario PW-HPHT-01 Humidikit Bundle is perfect for humidifying your guitar. With this bundle you are able to automatically humidify your guitar whilst on the go. You can track the temperature/humidity using the free Humiditrak App(download in the app store). Bovedas patented two-way automatic humidity control technology maintains the ideal humidity level inside your instrument. Perfect for preventing cracks in your guitar. Please note: Mobile phone not included.