This is a wonderful pedal tuner. It silences the signal when it is on and doesn't seem to effect your guitar's tone when it is off. It does just what it is supposed to do.
All Snark 4 Models follow
It is definitely a handy thing to have to tune quickly, quietly and without trouble.
The Snark SN-5 is a chromatic clip on tuner for any stringed instrument, with a lighted display and it is super easy to use.
Clip it on, turn it on, and pluck a string. It's that simple. Good for quick alternate tuning, to say drop d, or open e, etc.