Unexplained boxes and sets?

ИВАН_ВОДКА

i tried to buy some of them, im wondering they contain only green items, without any sets?

i tried vr10 Unexplained Heavy Armor

ИВАН_ВОДКА

or i was wrong. no sets from this boxes?

its from vendors in PVE locations

phaneub17_ESO

They're just random green gear, if you want to find green sets you have a better chance at running around a zone opening treasure chests in the field or farming in public dungeons.