The Peterson AutoStrobe 490 is agreed by music students, technicians, and professionals to be the standard by which all tuners are measured. Only Peterson could bring you the kind of real- time intonation critical enough for ear training use. Enjoy hands-free note selection for fast, accurate tuning of instruments. Other companies may boast of their strobe tuner capabilities, but buyer beware! The AutoStrobe 490 is a truly stroboscopic mechanical tuner capable of fundamental and overtone display. Key features include mutable throughputs for in-line (yet silent) tuning during performances, automatic image clarity and contrast control which internally compensate for optimal viewing over a wide range of source pitch and volume, improved clarity for upper and lower register notes (our +2/-1 display feature shifts the strobe patterns into more visible middle ranges so that bass note patterns can be displayed two octaves higher and treble note patterns can be displayed one octave lower in strobe display), and easy transposition (strobe patterns appear at the correct note for Bb, F, and Eb instruments).