When applying the overprint on the stamps, many times we had an error: Inverted overprint, Double Overprint, sometimes some characters were missing from the overprint, sometimes the overprint was applied on the wrong stamp... These error overprints were either intended or not. Unintended are worth more.
Here we have two valuable nice pairs. One is missing the R in Grand and the other is missing the digit 2. These two errors are catalogued and have a good value. Furthermore they got extra value because they are attached to a normal stamp!
Here we have 3 nice inverted overprint on Sower French Stamps. They are looked for specialised collectors. Also you have 2 nice double overprint stamps.
Here you have a nice used vertical pair, it has a striking variety, look closer between the 1 and P on the second line in each stamp, they are different, the 1 and P are closer in one. This variety is not catalogued.
Here you have a nice pair where the overprint is on one stamp only. If you separate the stamps, you will loose the error.
Also you have a nice vertical pair, the overprint is on a Syrian stamps not on Lebanese stamps!!!
Then you have a vertival pair where the R of Republique is missing on one stamp. Finally you have a nice used postage due stamp in Beirut where the overprint is inverted.