Attention: Tuning pegs are conical, please do not measure the pegs at the top square but where the tuning peg goes into the instrument (approximately centre).
The matching tuning keys and tuning hammer are also conical on the inside, in addition, the 4 inner walls are grooved in the middle, therefore the confusing dimensions. The specification e.g. 5.2 mm is measured at the outermost end without taking into account the grooves inside. Of course, the lowest opening of the tuning key/tuning hammer is wider than the middle area. For concert zither
White beech handle, T-shape, suitable for swivel diameter 5.5 mm