This driving ring is used in the old switching system.
New switching system is based on part 18947 - Technic Driving Ring 3L.
Click on a colored part below to see the Sets and MOCs that use part 6539 Technic Driving Ring 2L in that color. You can find an overview of all LEGO Colors here.
If a color is missing, it probably needs to be added to a Set Inventory.
This part has been used by MOCs in the following colors but not officially released.