This commemorative cover was issued to celebrate the Queen's visit to Milton Keynes. The cover design by Mandy Searles features "Hats fit for a Queen". The winning entries in a design competition organised by the Milton Keynes Citizen.
These are complemented by the "Diamond Wedding" stamp issue. On each of the stamps Her Majesty can be seen wearing a hat of course.
The stamps have been cancelled on the day of the Royal visit with a specially sponsored Royal Mail handstamp.