The Guitar Tone Completer Sound Opener simulates the vibrations of real-life guitar playing, the full sonic potential of the HK-01The tone completer has the buzz of the guitar world! Simulates the effects of real-world playing to bring out the best in your guitar. This revolutionary play-in simulator is based on the observation that the more an acoustic instrument is played, the faster it reaches its full sonic potential (its play-in period). The tone completer applies direct vibrations to the guitar with controlled frequencies to simulate the effects of real-world playing. Many players report increased volume and dynamic range in their instruments after using the device between playing sessions. Built-in Battery: 800mApplication: Guitar/UkuleleColor: BlackMaterial: ABSMesize: 7.5x5.5x5cmPackage Contents:1 x Sound Bottle Opener1 x Connection LineNote: Do not use while chargingOnly the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement error is +/- 1-3cm.