This is a bottle of Glendronach 15yr at 40% alc/vol. Its not the current production which is the Glendronach 15yr Revival at 46% alc/vol.
I know that Glendronach has closed and changed hands several times.
What is different? When was this bottled? I'm thinking around 2002 and 2003 when Glendronach last reopened.
My google searches only tell me it is rare.