In July 2017 Ebay seller bertramg2006 from Greiz in Germany was trying to sell this sample Bahrain plate.
He does not know where it comes from but unfortunately it is a sample for the 1969 series.
There are hundreds of samples that were made for this series and many of the different vehicle categories were never used or they were used but with different colours from the samples.
This one is a public transport plate (mostly buses) and although it is the correct colour, the registration should be in the batch reserved for these vehicles and it does not have the official stamp in the front of the plate.
An unused and incorrect sample probably from an old timers collection and collected in the 70s.