 The medal had an oval medallion, consisting of the cypher of the reigning monarch in silver gilt surrounded by a silver rope tied with a reef knot at the base and surmounted by a gilt crown which acts as the ribbon suspension, hung from a ribbon which was dark green until 1941 and green edged white thereafter.Originally, fifteen years' service was required (not counting service as a midshipman), with wartime service counting double.Clasps to the Reserve Decoration were awarded to recognise further periods of 10 years' service after the first award.