Les, re the Korg CM-100L Tuner Clip: Sorry if I wasn't clear. The plug goes into a jack on an electronic tuner. There is a pickup in a rubberized clamp on the other end of the wire. The clamp attaches to your tenor banjo, guitar, trombone, kazoo or any other un-amplified instrument.
- Phil
(The Tuner Clip is only useful, of course, it you have an electronic tuner with a jack. Other than headstock tuners, the electronic tuners I've used all have a jack so one can plug an electric guitar into them)