This microfilm is 10-12mm square in size and the only true or real microfilm of it's type. It is a highly knowledge based replica of the original that is of even greater quality than the original. Of course we didn't have the added stress of looking over our shoulder with one eye while we were making. It contains a code or cipher used by KGB agents during the cold war. This microdot is a reproduction of the microfilm found in the famous nickel that was mistakenly given to a paperboy in 1953 from whom the FBI obtained it. From this coin, the microfilm that was found inside, and information obtained from defecting russian spy agents, a very dangerous Russian spy ring was broken. This was probably the biggest cold war win for the US in the world of microdots to that point. Visit the FBI website for the entire story as they tell it best.