This clavichord is fretted, and there is a similar known clavichord in private possession by Rosenau dated 1772. Fretted clavichords of such a late date are rare in Sweden.
Vertical tangents positioned in the middle of the keys give a temperament with less difference between chromatic and diatonic semitones than in meantone. Chosen here are chromatic semitones of 89.5 cents and diatonic semitones of 107.5 cents, which corresponds to tempered fifths of 698.5 cents.
For a discussion of this choice see Clavichord International Vol.10 No.1 May 2006, pp. 17-20: HansErik Svensson, Comments on the tuning of some fretted clavichords in the Stockholm Music Museum.