From Manufacturer
As the name "Switch" hints, Westcott has introduced a line of softboxes designed for the rapid setup and swapping out of different brands of strobes and speedlights in seconds. This Rapid Box Switch / Beauty Dish Switch Insert for Speedlites Speedlites is one of thirteen all-metal inserts available for different brands of flash heads. Instead of using a full dedicated speedring, this insert slides quickly into your Switch's rear tabs and secures in place with the Switch's thumb lock.
UPC: 812735028309