Games : What does Gaun's Pledge do?

I just noticed the ring Gaun's Pledge in my inventory, I suspect it appeared because the Preorder Bonus DLC was installed.

From the description I gather that it provides protection in some form, but the description of the actual bonus is rather annoyingly useless:

Gaun's Pledge: Grants Gaun's Pledge

I didn't notice any attributes changing when I equipped the ring. So what does Gaun's Pledge do and exactly what bonus does it provide?