The Samson CM40 Chromatic Guitar Tuner and Metronome brings precision tuning and metronome capabilities together. The Samson CM40"s compact, easy-to-use design makes tuning any stringed, woodwind or brass instrument, as well as metronome training, a breeze. As a chromatic tuner, the CM40 offers a variety of impressive features, including two modes of tuning: Tone (manual) and Meter (automatic). When using Tone mode, the CM40 guitar tuner automatically recognizes the note you"re playing, while Meter mode allows you to select a reference pitch. Use its on-board microphone to adjust acoustic instruments and its 1/4-inch input connector for electronic instruments. Also, the CM40 puts a flat tuning/transposition setting at your fingertips. Ultimately, the CM40 always generates a smooth, real-time response with precise tuning accuracy that can be calibrated between 430 and 450 Hz. The Samson CM40 also functions as a metronome. Practice along with tempos ranging from 30 to 250 bpm using the tuner"s built-in speaker with volume control, 1/4-inch output and 1/8-inch headphone jack. In Beat mode, you can choose from ten different time signatures. And by using the Rhythm function, each time signature contains nine rhythm variations for practicing a wide range of styles. You will master your timing, no matter the time signature or style of music your playing. Designed with a large, full color LCD display, as well as LED pitch/beat indicators, the CM40 can be easily used in any environment, including a dark stage. It also features an integrated kickstand for better viewing. Lastly, a convenient auto power-off function conserves the two included AAA batteries that power the CM40 if it is not in use for 10 minutes.