Mounted on the camera viewfinder, the DK-17M increases viewfinder magnification by approximately 1.2x for added viewing precision. The DK-17M is designed for use with the D1X, D1H, D2X, D2H, D2Hs, F4, F5 and F6 cameras. It supports the safety lock feature available with the F6, D2X, D2H and D2Hs.