The main features of Rolex watches are precision, durability and water resistance, so there is no back-through money on the whole line (only a few art and limited styles). The purpose of doing this is to focus only on the quality of the watch itself, which is its main selling point. Since there is no back wear, there is no need to move the K gold, because it can't be seen from the outside. So, there is a 99% chance that your watch is not real.