Thank you for viewing. This is a convex mirror that covers blind spots with a flat mirror. Simply stick it to the mirror with double-sided tape, and you'll be able to see things you couldn't before. This is a standard item in the U.S.A., not only for ordinary cars but also for large trucks and trailers. Depending on how you use it, you can attach it to a computer or entrance, expanding the area you can see. This item was stored at home. It is unopened. Please understand.