Value wise, this is the best I can find around.  I went to Rite-Aid across the street and the cheapest I can find is double the price of this pair.  Polarizer works great.  spring loaded and easy to clip.  Came with a hard clear plastic case. Just perfect for my glasses.

54mm x 31 mm is equivalent to 2.1 inches x 1.22 inches.  But the actual measurement is close to 2.1 inches by 1.4 inches.

Cons:
- The metal part part seems made of crude black painted steel, not very polished.  But that is what I expect for what I paid for.