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This is a part which tightens the shift selection of the gear shift lever of your T3 Vanagon (83 and up). They are little plastic tabs which act as a guide for the bottom of the shift lever in Syncro models and Vanagons with 4 speed manual transmission. In the models between 83-85 check which kind of selector tabs you have as there might be a different style (251 711 173 C).
They come as a pair with mounting pins or in a glue on version as a kit with epoxy glue.
Part Numbers: 251711271D