The D'Addario NS Micro Tuner 2 Pack offers a pair of tuners designed for improved accuracy, faster response and expanded calibration range with a visual metronome mode and an improved ratchet design. A highly sensitive piezo transducer and easy-to-read multi-color backlit displays allow smooth and highly accurate tuning in noisy, dim or well-lit environments. The micro design and reversible screen allow your tuner to hide effortlessly behind or mount on the front side of the headstock. A 360-degree swivel mechanism and adjustable padded clamp offer optimal viewing angles and maximum positioning flexibility. As a result, the NS Micro tuner is equally at home on left- and right-handed instruments as well as on small and large headstocks. The NS Micro tuners are powered by a readily available CR2032 battery (included) and provide maximum battery life utilizing an auto-off function, shutting the tuners off automatically after several minutes from power up.