Service Dress became a smart uniform for wear on the streets, and on moderately formal occasions. After World War II the coloured, full dress uniforms were again reintroduced for ceremonial occasions by the Brigade of Guards and to a limited extent by regimental bands. Officers (and later senior non-commissioned officers) resumed wearing mess uniforms in traditional colours from about 1956 on. These are still worn, although regimental amalgamations have led to numerous changes from the pre-war models. With limited exceptions, the unique regimental full dress uniforms finally disappeared after 1939; today they are only generally worn, on ceremonial occasions, by the Bands and Corps of Drums, by certain representatives on parade (e.g. some regimental Pioneers, or those forming a guard of honour) and by the regiments of the Household Division. In most regiments they were replaced by a generic dark blue uniform known as No 1 Dress. This dated back to plain "patrol" uniforms worn by officers before 1914 as an informal "undress" uniform. An early version had been worn by some units in the 1937 coronation of King George VI and Queen Elizabeth but had not been made general issue at the time. In the form adopted after World War II, most regiments were distinguished only by coloured piping on the shoulder straps, coloured hat bands, buttons and badges. However Scottish regiments retained their kilts or trews as well as the distinctive doublets (in "piper green" or dark blue) of the former scarlet uniform. Rifles regiments had dark green uniforms and cavalry retained a number of special features such as the crimson trousers of the 11th Hussars or the quartered caps of lancer regiments. A white, lightweight tunic (No 3 Dress) was also authorised for use in the tropics, or during the summer months in warmer temperate climates (such as Bermuda). The blue "home service" helmets were not worn as part of the No 1 dress uniform, except by members of some bands or corps of drums which retained their old full dress uniforms, at regimental expense. English Rifle regiments were amalgamated into the Royal Green Jackets, which continued to wear a dark green dress uniform, and black buttons and belts. Changes have brought the Royal Green Jackets and The Light Infantry together into a single regiment The Rifles, which continues to wear dark green. Berets were introduced initially into the Royal Tank Corps in the First World War