12 inches in diameter and in working condition. Purchased at an estate sale of a long ago closed auto repair shop. Thermometer was still hanging on a wall where it has probably spent the last 50 or so years. In my opinion it is very presentable. I only wiped it down with a wet rag for pics. It does show some dust and very light soiling to face and most all you see, is to the underside of the glass. It shows tarnish to aluminum outer ring and paint drips to back side, should clean up good. Like I said, very presentable as is, but if you could take this apart and clean inside and out, I\'m thinking close to near mint. I also have a Pam Pennzoil thermometer listed and will gladly combine shipping on multiple wins. Thanks for looking.