I have one without a truss rod. neck is still good but at some point fixed because i can see a screw which looks newer than the guitar.sounds good and intonation is good . I'm wondering if it was produced prior to 1955. there is another label on the inside that says cs. hudebni nastroje
harmonica, horovice. there is more writing on the label but hard to read. Any ideas on production date. It does not have a slotted headstock.