The Profoto Adapter Ring Inner diameter is 5.98in/152mm, replaces the same size of different brands of adapte rings, such as Bowens, Elinchrom, Balcar, Hensel, Einstein, Broncolor, Comet, etc. Usually used to replace the adapter ring on some photography lighting accessories, such as softboxes, spotlights, etc, to make it compatible with Profotos Flashes, Monolights, and LED lights.
Note: The 152mm Profoto Adapter Ring can be compatible with FOMITO Optical Snoot.