1st Class Post & Go stamp with self-adhesive gum. These stamps were fist issued in 2008 and since then the Royal Mail have issued hundreds of different stamps to commemorate events and UK nature themed stamps such as birds, wild flowers, farming and Christmas themed etc.
The image shown is just an example. The stamps are taken at random from stock so you could receive absolutely any design or theme that the Royal have issued since 2008.
Note: These stamp will remain 100% valid for postal use after 31st July 2023