The Badge of the House of Windsor (the ruling royal house of the United Kingdom and the other Commonwealth realms), as approved by King George VI in 1938. In the style used from 1938 to 1952 and the again from 2022.

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Although the Sovereigns of the House of Windsor (this dynastic name was adopted by Royal Proclamation on 17th June 1917) have used various old royal badges only one or two new badges have been adopted that for Wales and the following badge for the House of Windsor, which was approved by King George VI on 28th July 1938: On a Mount Vert the Round Tower of Windsor Castle argent, masoned sable, flying thereon the Royal Standard, the whole within two branches of oak fructed or, and ensigned with the Imperial Crown.

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(J.P. Brooke-Little, 1954, Boutell's Heraldry, Frederick Warne: London and New York, pages 216-217)
Own work, based on one found on this website: yeomenoftheguard.com. ([1])
Sodacan