Here is a 1972 U.S. Proof Set. These are becoming fewer and fewer because the proof sets in a lot of cases are selling below the price if each coin is sold seperately. And that is what a lot of dealers and some collectors are doing. They are breaking the holders and selling the coins individually. Its very easy to check on this, by checking the Gray Sheet and adding up the value of each coin. In the furture, these sets will soar in value. I would not sell this set but I am selling my collection because on the 13th of March I was 79 years young.