This is a very unusual bank notes. It has two unusual features. First, it a very unique denomination (however, similar have been noted in bank notes of Netherlands and Bangladesh) and secondly, the size is to make sure it does not fit a wallet i.e 159 mm by 159 mm.
This is a 60 Baht note from Thailand. This is a 1987 Commemorative issue from the King Rama IX 60th Birthday.
The note has an issue date of 5 December 1987 but apparently not disclosed. On the front King Rama IX is setting on the throne and on the back the Royal Family can be seen with the subjects.
This note was added to my collection in April 2012 at Maastricht, The Netherlands.