Polytune Clip Q&A "What batteries does it use and how's the battery life?" - YouTube
Amazon.com: TC Electronic POLYTUNE CLIP Clip-On Tuner with Polyphonic, Strobe and Chromatic Modes and 108 LED Matrix Display for Ultimate Tuning Performance : Musical Instruments
Duracell 2032 Replacement Battery for Snark, Polytune Clip Tuner – Guitar Gallery of Alabama
TC Electronic PolyTune Clip On Tuner - 713803229850