GARY FONG Lightsphere Collapsible Flash Diffuser LSC01 and a Cleaning Kit + a BONUS 4 Pk. AA Batteries for Canon, Nikon, Olympus, Pentax, Nissin, Yongnuo and Sony Flash Units Universal Fit - base mount opening is highly strechable (2"x3.25") fitting most flash units Utilizes patent pending sizing ribs that provide an equally tight fit to several sizes of flashes without the need for straps or bands. The Inverted Dome is included with every Lightsphere Collapsible Purchase. Works with your existing accessory domes - AmberDome, PowerGrid, and can be mounted right-side up or upside-down. Collapses down to a 1 inch thick ring allowing for easy storage