Other Ranks Head Gear
In the early days of the 2nd Boer War a Foreign Service helmet with a khaki drill cover was standard issue. A khaki drill neck curtain was also issued with the helmet, but rarely used. By
the end of the war the helmet had been replaced by a slouch for almost all Regiments.

here   for original examples of Imperial Yeomanry, and locally raised units shoulder titles often used on slouch hats.
Foreign Service Helmet Khaki Cloth Neck
Field Service Cap