The 'chest piece' (plastron) on uhlan uniforms was removeable, and not worn with certain orders of dress, in the same way that hussars did not always wear the pelisse).
Also, the ornament on officers' uniforms is often a different colour, or different shade of the same colour, from that on other ranks' uniforms. For instance, the officers of HM Life Guard Hussars had gold seam stripes on their breeches, while other ranks had yellow.
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