This Chromatic Clip-on NS Micro Universal Soundhole Tuner by D'Addario is a newly designed, Ned Steinberger design with great features. Mounts discreetly in your soundhole. The full-color display is a mere 1/4 inch x 5/8 inch and easy to view looking down at your soundhole. It is a clip-on type that picks up vibrations through a highly sensitive piezo transducer. These are always less susceptible to interference from noisy environments than other tuners. They are extremely accurate and will work with virtually any instrument that has a soundhole (guitar, bass, mandolin, ukulele, etc.). The multi-color backlit LCD screen makes tuning easy in dim or well-lit environments. Can be user calibrated from A410 to A480. Uses one CR2032 battery (included). Also has an automatic shutoff feature that conserves battery life by shutting down after 10 minutes. This is a very handy and useful tuner that can be left with your instrument when stored. I really like the bright display and how quick it reacts to the tone. MSRP $44.10.