Extending the effective focal length of select Tamron lenses, this Canon EF-mount Teleconverter 2.0x enables you to get even more reach out of your telephoto lenses. The dedicated design retains communication between the lens and Canon EF-mount cameras, including auto-exposure metering and Vibration Compensation image stabilization, and both one low dispersion element and a BBAR coating has also been incorporated to maintain image quality. Additionally, this teleconverter also features a dust- and moisture-resistant construction, matching the lens, to benefit working in harsh environmental conditions. Lens Compatibility SP 150-600mm f/5-6.3 Di VC USD G2 SP 70-200mm f/2.8 Di VC USD G2 100-400mm f/4.5-6.3 Di VC USD 2.0x teleconverter doubles the reach of the select lenses with only a two-stop loss in exposure One low dispersion element is included in the optical design to reduce chromatic aberrations and color fringing BBAR coating maintains image quality by reducing flare, reflections, and ghosting Dedicated design retains electronic communication between the lens and camera to support AE and VC functions Weather-resistant design for use in inclement conditions