Since 1987, she has not worn uniform, but wears the Brigade of Guards badge, a large brooch representing the different regiments that participate (Grenadier Guards, Coldstream Guards, Welsh Guards, Irish Guards, and Scots Guards). Her 80th birthday in 2006 was marked by a large flypast of 40 planes led by the Battle of Britain Memorial Flight and culminating with the Red Arrows. It was followed by the first feu de joie ("fire of joy") fired in her presence during her reign, a second being fired at her Diamond Jubilee celebrations in 2012. In 2008, a flypast of 55 aircraft commemorated the RAF's 90th anniversary. The Unit presenting the Colours usually begins Troop practice in April provided that the company does not have other prior military operations. The entire parade will rehearse in full dress at Horse Guards Parade before the Major General's Review, such rehearsals are referred to as Guard Mount from Horse Guards. The Major General's Review and the Colonel's Review are scheduled on the Saturdays two and one weeks preceding the Queen's Birthday Parade respectively. The salute is taken, respectively, by the Major-General commanding the Household Division and the Colonel of the Regiment which is trooping its colour. On the day of Trooping the Colour, the Royal Standard is flown from Buckingham Palace and from Horse Guards Building, while the Union Flag (colloquially known as the Union Jack), is flown from public buildings as well as the flags of the British Commonwealth of Nations, especially in recent years. "Nos. 1-6 Guards" - six companies of Foot Guards, each comprising 3 officers and 71 other ranks  - line two sides of the perimeter of Horse Guards Parade in an extended "L" shape. This recalls the defensive formation known as the "hollow square." All six companies are collectively commanded as "Guards..." and individually by company number, e.g., "No. 3 Guard..." Up to eight Guards have taken part, the number varying over the years: six in 1939, five in 1954, seven from 1963 to 1967, and then eight until the 1980s. The battalion trooping its colour in any given year is No. 1 Guard. During the parade, they are referred to as 'Escort for the Colour' (and, once they have collected their colour during the ceremony, as 'Escort to the Colour'). At the outset, the colour is held by the Colour Party - a colour sergeant and two other guardsmen of No. 1 Guards, standing well-spaced on the northern side of Horse Guards Parade.