The Nikon TC-17E II 1.7x Teleconverter for AF-S and AF-I Lenses was designed exclusively for use with AF-S and AF-I lenses, and completes the Nikon lineup of 1.4x, 1.7x, and 2.0x compact teleconverters. This teleconverter will maintain full metering and focusing with compatible cameras and lenses, and will also support the VR function found on many of the newer professional lenses. The AF-S Teleconverter TC-17E II allows focal length to be extended by a factor of 1.7 times while retaining a sense of overall comfort in the hand. Many such teleconverters can also have a detrimental effect on the speed of the lens, however the AF-S Teleconverter TC-17E II makes available f-stops only 1.5 stops slower. NOTE : Autofocusing only possible when used with D1, D1X, D1H, D2H, D100, F5, F100, N90s, N80, N75 and N65 ;AF SLR Cameras ( or any newer models ).