It was units of the Guards Armoured Division that lead XXX Corps during Operation Market Garden and are shown in 'A Bridge Too Far' as the Irish Guards and Grenadier Guards.
Although the Guards armoured battalions wore black berets with regimental cap badges, the Units of the Guards Armoured Division were not part of the Royal Armoured Corps. They would not (perish the thought) have worn the RAC Mailed Fist cap badge.
https://en.m.wikipedia.org/wiki/List...n_World_War_II
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