Anyone have any idea what the 2nd button on the Pro 3 pen does?

[Pwersha]

Currently I have a Surface Pro 2, which has a single button on the pen for a "right" mouse click. I am curious why there are now 2 buttons. None of the reviews that I have seen have made mention of it.

Any idea?

 

[Pwersha]

Of course, as soon as I post, I find the answer.

The 2nd button is erase, I guess using the other end of the pen no longer works for erase.

Source: Surface Tablet Pen - Designed to Be More Natural Than a Stylus

 

[GoodBytes]

The top pen button starts OneNote. Second button is eraser. N-Trig doesn't have eraser functionality. at the top. They can't have it, as they need room for the battery.