Rolex reference 16710R?

[sheldonsmith]

From my webpage at https://www.minus4plus6.com/paracromblu16710.php#crown

The Crown Method
Another method for discerning a 3185 with the 3186 movement is through the the Crown Rotation Method. This method is another way to discern the type of movement without having to remove the caseback. Because the calendar and hour-hand setting mechanism was redesigned in the 3186 movement, the number of turns of the crown to turn the 12 hour hand is different on a 3186 than it is on a 3185.

To perform this test, unscrew the crown such that the crown is in the hand setting position. With the crown face-up, count how many hours the hour-hand travels with one full revolution of the winding crown.

3185: one complete crown revolution makes the hour hand jumps 6 timezones/hours

3186: one complete crown revolution equals 8-9 timezones/hours
This tip was provided to Minus4Plus6.com by Ed who discovered this method on a French watch forum.

~ Sheldon