Glamoured Studded Leather

Source: D&D 5.2 SRD Magic Items

Armor (Studded Leather Armor), Rare

While wearing this armor, you gain a +1 bonus to Armor Class. You can also take a Bonus Action to cause the armor to assume the appearance of a normal set of clothing or some other kind of armor. You decide what it looks like — including color, style, and accessories — but the armor retains its normal bulk and weight. The illusory appearance lasts until you use this property again or doff the armor.