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Beginning with the Afghan War of 1878, the British Army began adopting light khaki uniforms for tropical service. This innovation arose from experience fighting irregular forces in India and Africa, the invention of smokeless powder and the increasing effectiveness and usage of rifles. In 1902 a darker shade of Service Dress (SD) was adopted for field and ordinary use in Britain itself. The scarlet, blue and rifle green uniforms were retained for wear as full dress on parade and walking out dress when off duty. When khaki web carrying equipment was introduced, the earlier, white or black leather carrying equipment was reduced to just the belt (and sometimes a bayonet frog), for wear with the dress uniform. As with the earlier uniforms, the officers' uniforms differed in quality and detail from those worn by the Other Ranks. Officers purchased their own dress uniforms from regimentally approved tailors while other ranks were issued all orders of dress from government stocks.