Cherry 2jd is 28-30mm. 2JD means black cherry with double grooves. J is the grading standard used by Chile, New Zealand, Australia and other major cherry producing countries. The more "J", the bigger the cherry. D stands for black, D stands for darkness.
When choosing a cherry, you should look at the color of the fruit stalk. Fresh green fruit stalks are the freshest. This cherry has a relatively short picking time.