11/16” with name of maker on reverse “Whitehead-Hoag.” Below this is the word “Sterling.” After the surrender of Japan and the end of WWII as the project wound down, each of the approximately 132,000 project members received one of these pins. Vast majority received a brass pin but this scarcer version in sterling was given to those who served longer than 1 year. Pin is .75” in dia. Project participants ranged across the country from areas such as Columbia University to Clinton Engineering Works in Oakridge, TN to New Mexico. Historic, scarce and essentially Mint. Our brass version in Auction #199 realized $247.50 plus buyer’s premium.