The Seiko ST01 Tuner is a handy personal tuner complete with key-ring that you can take with you wherever you go. Ultra-Compact & Easy to Use with a Metal Face-plate. Simply, press power switch to turn on/off. Input sound of instrument into built-in microphone. Indicates name of note and deviation in cent. LED light changes colour when in tune. Easy to use, readily accessible, and the key ring is included.
 
FEATURES:
Tuning Range: A0-C8
Pitch Shift: A4=440Hz
Auto Power off after 2 minutes without sensing a note
Auto Tuning Mode with Built in Microphone
So small it will fit anywhere!