This is a commemorative coin for the 100th anniversary of the submarine force within the U.S. Navy's 7th Fleet at Yokosuka Naval Base. It is 7cm in diameter, 5mm thick, and weighs 125g. I received this non-sale item from an acquaintance 25 years ago. The design and color scheme are excellent, and it's a shame to part with it, but I am selling it to declutter. There are some minor stains, but no scratches. If you are interested, please consider purchasing it. The cigarette case is for size comparison only.