King Charles III's new cypher has been revealed and over the coming years and months, it will gradually appear on Government buildings, state documents and on some post boxes.
The cypher is the monogram of a reigning sovereign and consists of the initials of their name and title and often includes a crown.
The new cypher features the King's initial C intertwined with the letter R for Rex – Latin for King – with III within the R denoting Charles III, with the crown above the letters.
It includes a Tudor crown adopted by King Charles – a more rounded version than the St Edward's crown worn by Queen Elizabeth II.
The start of Charles III's reign also heralds a time of change for companies that supply the Armed Forces with anything that bears his cypher – from cap badges and flags, to belts, medals, swords and sporrans.
The change in monarch affects the militaries of Commonwealth countries such as Australia and Jamaica.
British Army cap badges, including those of the Life Guards, Blues and Royals, Royal Horse Artillery, Royal Engineers and Royal Military Police will be modified to reflect the new cypher.
Royal Air Force cap and squadron badges will be affected. The current badges include the Queen's St Edward's crown, rather than the more rounded Tudor crown which King Charles has adopted in his cypher.
Changes are expected to be gradual, rather than immediate.
A Cabinet Office spokesperson said: "Where changes can be made easily, such as digital branding, they can be made immediately.
"Physical items such as signage or stationery will be replaced gradually over time as the need arises."
Regimental units will likely fly the Queen's colours for years to come. Even if they wanted to replace them – they couldn't do so any time soon.
Each standard takes six months to sew by hand and, from sporrans to swords, there are likely tens of thousands of product lines to change.