For the purposes of the Monk's AC bonus class feature, does the Gunman's Duster count as armor?

Question

I'm currently playing a Gunslinger with a dip in Monk and I'll be taking an unarmored approach to make full use of Wisdom synergy. The Gunman's Duster is a wondrous item worn in the body slot which provides a +4 armor bonus to AC. The Monk's AC bonus class feature says this:

When unarmored and unencumbered, the monk adds his Wisdom bonus (if any) to his AC and his CMD. In addition, a monk gains a +1 bonus to AC and CMD at 4th level. This bonus increases by 1 for every four monk levels thereafter, up to a maximum of +5 at 20th level.

These bonuses to AC apply even against touch attacks or when the monk is flat-footed. He loses these bonuses when he is immobilized or helpless, when he wears any armor, when he carries a shield, or when he carries a medium or heavy load.

Does this item count as armor for the purposes of this class feature?

Answer 1

I see no more reason to consider this armor anymore as I would a set of Bracers of Armor or a casting of the Mage Armor spell.

Just because it grants an Armor bonus to AC, doesn't make it Armor. Only things in the Equipment section under Armor are armor. This item doesn't mention anything about what Proficiency you need to wear it, it's called a "Wondrous Item" and it doesn't supply an Armor Check Penalty. Therefor, it is not Armor, just a Wondrous Item.