The O Ring flash Adapter creates a very special lighting effect, there are no electronics, no flash tubes and no cumbersome cables! It uses a clever system of internal prisms, reflectors and light-shapes to distribute the light emitted from the flash unit. Model: F175, is suitable for: CANON 550EX 580EX/580EX II + 1DS / 1D / 1V NIKON SB900 + NIKON D700 / D300 / D3X / D2X