This knob is used as a handle for the adjustment of the backrest in position for the Volkswagen Beetle between the years 8.1972 and 7.1975 and additionally for the years up to and including 7.1972 as a handle for the longitudinal adjustment of the seat.
For all other Volkswagen models mentioned, this knob is only used for the longitudinal seat adjustment. If you are in possession of an ambulance version of the Volkswagen Split Bus, this knob is also applied for the passenger seat, also for the longitudinal adjustment.
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