The K6 kiosk was commissioned in 1935 to commemorate the Silver Jubilee of King George V. The design of the "Jubilee Kiosk" needed to the first, true, universal kiosk, and one which didn't repeat any of the mistakes of the earlier kiosks. Although the K2 and K3 kiosks were undoubtedly asthetic and attractive designs they were costly - in the case of the K2 - and difficult - in the case of the K3 - to produce. Fortunately the Post Office again commissioned Sir Giles Gilbert Scott to design the new kiosk and he did not let them down with his design.
The K6 was similar to his design for the K2, but was smaller and had simpler detailing. The pierced crown on the dome was replaced with a moulded dome; ventilation slots were inserted below the "Telephone" where previously the pierced crown provided ventilation; the arrangement of glazing bars was altered for narrower outer panes and a wider inner pane; the moulding at the bottom of the door was omitted. This would make it cheaper to produce, and therefore easier to site across the country - it was lighter to transport and required a smaller footprint. The design was still unmistakably a Gilbert Scott design and would be a success.
Scott's K6 kiosk appeared in 1936, followed by a more vandal-proof Mk II version in 1939 and by 1960 some 60,000 examples existed. The Post Office allowed rural examples to be painted in different colours including green, yellow, white and battleship grey. Red was chosen to make the kiosk stand out against its surroundings in case of an emergency telephone call. The K6 became the most populous K-kiosk was is the most recognisable of all K-kiosk designs.
