On 10 February 1949, the Saar government announced a change to the German Road Traffic Permit Act (StVZO), which changed "SAAR" and "SA" to "OE". The Saarland's population speculated for some time what "OE" might stand for. Speculations ranged from "Occupation Est" to "Ost-Elass" to "Officellement Enregistré". However, in truth, the "OE" was used because the Saarland had been an economic union with France since 1947 and it was intended to therefore align the Saarland's number plates with the French ones. In France, the different "départements" were registered with double letters in their number plates. The plate "1532 OE 24 SA" was additionally supplemented by "SA", the international sign for the Saarland valid until 1957. However, the French changed the letter combinations to number combinations for the different "départements" in 1950 and these remained valid until 2009. This number plate was also used by a mining vehicle of the Geislautern pit - the 24 was the identification number for Volklingen.