does anyone know exactly what it does?. i was told it gives you wigs but they don't know how many or anything.

You'll get 5 random Wigs that are currently in the Hatbox. SubetaHQ has a list, but some of the wigs there are already retired from the Hat Box.

is it worth opening or selling?

i opened... got three wigs worth less than a million.. one worth almost 6 and one worth 3.. stuffed in my wardrobe