Kaidan KiWi+ Detent Ring for the KiWi+ QTVR Panoramic Tripod Head, #17

The KiWi+ detent discs add flexibility by providing click stops for a variety of lens combinations.
The disk selection chart details the number of clicks one would need for a certain size lens.
Each disc is slightly larger than a silver dollar. The discs are available with 2 to 22 stops.