There is not much to AC1200UB. Contents of the box are Quick Installation Guide, Driver CD, 1 meter of USB 3.0 extension cable and the actual RNX-AC1200UB unit.
It is worth to mention that the WiFi adapter was securely held in the sponge like holder and covered by a plastic sticker to prevent any accidental scratches. Installation Guide is very simple and you kind of have to read between the lines. As you have to install the driver from the CD and its not auto-ran from CD itself. AC1200UB has a Wireless Utility which could be installed from the CD as well as from Rosewill website (if you ever lose the CD).
The Rosewill AC1200UB is about 2 times bigger than your average thumb drive (~7.5 cm x 2.5 cm x 1 cm). Adapter comes with small cap to protect the USB 3.0 connector while in transport. Entire shell of this unit is made from ABS plastic. To indicate the Power and Access AC1200UB has a small green LED on top. This particular unit offers WPS (easy setup) function which most of the new WiFi routers support.