Peavey humbucker model - Manual (Page 19)

Tuning Machine Adjustments
Over time, tuners can become loose. Get in the habit of checking the tension with every string change.
If you notice a change in the tension of a tuner, use a small flathead or Phillips screwdriver to tighten it
(turn clockwise) or loosen it (turn counterclockwise) accordingly. Warning: While the screw should be
snug, do not overtighten, as you may strip the screw.
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