Battledress (BD), later named the No. 5 Uniform, was the combat uniform worn by British Commonwealth and Imperial forces through the Second World War. Battledress was introduced into the British Army just before the start of the war and worn until the 1960s. Other nations introduced their own variants of battledress during the war, including Australia, Canada, India, New Zealand, South Africa, and the United States and after the Second World War, including Argentina, Belgium, Norway, the Netherlands, and Greece. It was worn mostly but not exclusively in temperate climates. In some armies it continued in use into the 1970s. During the Second World War and thereafter this uniform was also used for formal parades (including mounting the guard at Buckingham Palace) until the re-introduction of separate parade uniforms in the late 1950s. From the early 1930s, the British War Office began research on a replacement for the Service Dress that had been a combined field and dress uniform since the early 1900s. Initially conducted on a small scale over several years, some of the ideas tested included deerstalker hats and safari jackets. After extensive field trials of other uniforms, Battledress, Serge (often referred to as 1937 Pattern, albeit incorrectly) was adopted just before the Second World War. The uniform was designed with the needs of mechanised infantry in mind, and was inspired by contemporary wool 'ski suits' that were less restrictive to the wearer, used less material, were warm even while wet and were more suited to vehicular movement than Service Dress. Attempting to create a more standardised uniform across much of the British military, it was composed of a fairly streamlined short jacket of wool serge that buttoned to the outside of high-waisted wool serge trousers. The sleeves of the jacket had a forward curve built into them so that they were more comfortable to wear prone, shouldering a rifle, or seated holding a steering wheel for instance, although they tended to show multiple wrinkles near the inside of the elbow when the soldier's arms were held straight at the sides.