Mostly produced between 1968 and 1973, so called "Red" Submariners have become one of the desired versions due to the distinctive red print on the dial. The huge majority of these were feet first and in fact red meter first dials according to scholars represent a very small portion of the total production. This particular example is even rarer due to the fact that it is a Mark I (serial range estimated around 2.07 to 2.2 million) which has the following characteristics: elongated closed 6's, a long and curved F that covers the letter T and a distinctive font. Without a doubt the most collectible and early versions of the 1680 Red Submariners.