Amazon.com: Real Tuner - Chromatic Clip-on Tuner for Guitar, Bass, Violin, Ukulele, Banjo, Brass and Woodwind Instruments - Bright Full Color Display - Extra Mic Function - A4 Pitch Calibration - Transposition : Musical Instruments
guitar tuner microphone, with on off switch. | eBay
Microphone Guitar Tuner
5 Free Online Guitar Tuner to Tune Guitar using PC Microphone