The front of the packaging for the RM850 gives us quite a few highlights of the unit, such as it being low noise, fully modular and Corsair Link ready.
On the back, we find that the fan doesn't engage till the power supply hits 40% load. This will keep the noise down most of the time, until something CPU and GPU heavy is started.
The right half of the back is mostly for other languages, but it does give us the I/O specifications too.
Corsair lists the connector availability on the top of the box.
Flipping to the bottom, we find a little bit more out about the unit. Also note that there is a chart on the right that shows where the unit sits in relations to all of Corsair's offerings for power supplies.