The white version of the Korg AW2G Clip-On Chromatic Guitar Tuner is designed to clip directly onto the headstock of a guitar. It picks up sound with either its built-in microphone, or its vibration-sensing piezo sensor (which is useful in noisy environments). It runs on an included easy to replace CR2032 lithium battery for up to 150 hours. If you forget to turn off the AW2G, it will automatically power itself down to save energy.
A built-in double ball-joint and meter reverse function allows you to position the tuner in many different angles.
The device can be calibrated for a variety of different concert tunings. The display is backlit, making it easy to read in any setting. The light can be dimmed, turned off, and set to only get bright when a signal is detected.