Opteka SB-1 Universal Studio Soft Box Flash Diffuser for Canon EOS, Nikon, Olympus, Pentax, Sony, Sigma, & Other External Flash Units Universal Studio Soft Box Flash Diffuser Provides soft even flash illumination One size fits all. Attaches with the included velcro strap and grip band Folds down flat for easy storage and portability Dimensions: 3.5" X 5"