0HD-16TC-XLH 1.6X HD Tele-Converter, Canon Bayonet Mount
Add the 1.6X Tele-Converter to the front of your zoom lens to shift its focal range in the telephoto direction. The perfect tool when it's inconvenient, dangerous, or even impossible to move as close to the subject as you'd like. There is no appreciable light loss. Note that the Tele-Converter offers partial zooming, vignetting will occur at mid-range through full wide angle.