It will only take one set. Some come in pairs so that you can remove one when using a filter. The different balance rings are different weights and thread diameters which is what makes them dedicated to specific lenses.
Thanks, I got it and obviously its difficult to tell if it balances well with the zoom extended. For anyone else who was thinking about using this ring with X5s the gimbal makes an odd sound for about 10 seconds just after initial calibration. Sounds like its being overworked! Not filled with confidence but I'll see how it goes...
On that subject, the 2 part ring for the Olympus 9-18mm is odd...
Indicates the "cap" going on the back of lens... do they mean back of Gimbal? Buy Zenmuse X5S Balancing Ring