
Tamron-F 1.4x C-AF1 MC4 teleconverter for Canon EF
This Tamron-F 1.4x C-AF1 MC4 teleconverter sits between your camera and your lens and provides a 1.4x focal length boost (at the price of one stop of light). Works on most EF cameras and many EF lenses, though compatibility and results will vary from lens to lens.