How it works... This fine tuner lever is strung onto a swivel pin. The lever is the part that pivots (pulls) away, and stretches the string to raise the pitch while fine tuning. The Kahler fine tuner screws into the back of it.
FYI: There are two types of levers to choose from. One lever has a course 6-32 thread pitch and one has a fine 6-40 thread pitch. The levers all look the same except for the threads so be careful to observe correctly. Course or fine. Lever threads are harder to see than a knobs head type, so look at the knobs to help you discover your thread pitch.
Understanding thread pitch and size... The first number, in this case "6", is the diameter size of the shaft (similar to wire sizing) and the second number signifies how many threads or winds per inch of shaft. So its easy, 32 rotations around the shaft per inch is courser than 40 crammed into the same inch. Get it?
The rule of thumb is... if the stock fine tuner knobs that you now have are flat top, then you have this 6-32 threaded 9417-32 lever and should use the 6-32 #8394 flat top knob. But if you have the dome top fine tuners now, you use the 9417-40 lever with a 6-40 #8385 dome knob. Of course if you do not have any knobs at all and are working in the dark, study the side by side image closely and try to match up the threading style with your lever. The top knob has the 6-40 fine threads and the lower flat top knob has course 6-32 threads.