Tuning pegs are conical; please do not measure the peg at the upper square, but at the point where the tuning peg goes into the respective instrument (approximately in the middle).
The matching tuning keys and tuning mallets are also conical inside; in addition, the 4 interior walls in the middle are grooved, therefore they have seemingly confusing dimensions. The indicated e.g. 5.2 mm is measured, excluding the grooves inside, at the outermost end. Of course, the lowest opening of the tuning key / tuning mallet is wider than the middle area.
For accord zither, dulcimer, kantele
White beech handle,T-shape
Square 4,2 mm
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