This extremely accurate tuner offers greatly improved resolution over anything in its class. It provides for flat and double-flat tuning, plus open D, E, G, A tunings. Shows both guitar string and fret icons for more intuitive operation. Display can be changed to accommodate 4- and 6-string basses, and it memorizes the setting eliminating the need to reset each time it is turned on. An auto-off function automatically shuts it off after remaining idle for more than 10 minutes.