'A thing of' is a very Irish way of describing an inanimate object, usually a container or packaging of sorts. Be it down to laziness, or actually not knowing the name of what the object is, this expression has many uses.
Used as an exclamation at something happening. Eg. at a hurling match when a person scores a goal in a humurous way a person can joke.
"Did ya see that, Up she flew and the cock flattened her!"