The unblinking eye set in this silver ring continually looks around. 

While attuned and wearing Alertness you gain the following benefits:

• You can see out of the ring as if it were another eye.
• You add your proficiency bonus to your initiative. 
• You gain proficiency in Perception (Wisdom).
• If you are already proficient in Perception (Wisdom) your bonus is doubled.

You only gain these benefits while your eyes are open, you are not blinded, and the ring is not covered.  For instance if you close your eyes you can still see through Alertness but you do not gain the bonuses to initiative or perception.  Similarly, if you don gloves or cover the ring you do not gain the benefits.  You can use the ring to look around corners by holding out your hand.  The Blinded condition works the same on you as anyone else.

Curse
You have disadvantage to saving throws against gaze attacks that rely on vision such as a  Medusa's Petrifying Gaze.

Notes: Bonus: Initiative, Bonus: Perception