Canon 2X EF Extender III Teleconverter (L Series Tele/Zoom Lenses)

Canon's 2x EF teleconverter built for L-series glass

The Canon Extender EF 2x III doubles the focal length of compatible L-series telephotos and zooms without adding a separate body or lens to your kit. At 11.46 oz and 2.1 inches long, it slips between your camera and lens with minimal bulk, and the dustproof, weather-resistant construction means it holds up in the same conditions your L-series glass was built for. The fluorine coating on exterior elements keeps fingerprints and smears from becoming a problem when you're working fast in the field.

Optically, the 9-element, 5-group design prioritizes controlling chromatic aberration, ghosting, and flare, problems that scale up fast when you're doubling focal length. Canon's built-in microcomputer keeps full communication running between camera body, lens, and extender, so autofocus, image stabilization, and EXIF data all function as expected. That's not a small thing when you're shooting at the effective focal lengths this extender produces from a 300mm f/2.8 or 500mm f/4.

Paired with Canon's longer L-series primes, this extender gives wildlife and sports shooters a second focal length without a second lens case. A 400mm f/2.8 becomes a 800mm f/5.6. That kind of reach, packaged in something that fits inside your camera bag alongside your existing kit, represents real working value.

Who It's For

Wildlife photographers working Canon's 300mm, 400mm, or 500mm L-series primes gain a second effective focal length on the same body, getting to 600mm or 800mm without hauling an additional prime. Sports shooters covering sideline or court action where tight reach matters will find the 2x multiplication factor gives them the compression and subject isolation that tighter focal lengths produce. Travel photographers already carrying L-series telephoto zooms can extend their reach significantly without adding a full lens to the bag. The weather-resistant construction makes this a practical choice for birders and nature shooters who work in rain or dusty conditions.

Key Features

• 9-element, 5-group optical design minimizes chromatic aberration and flare
• 2x magnification factor for extended focal length reach
• Built-in microcomputer maintains autofocus, IS, and EXIF communication
• Fluorine coating resists soiling, smears, and fingerprints
• Dustproof and weather-resistant construction for field durability
• Canon EF mount for L-series telephoto and zoom lenses
• 11.46 oz and 2.1 inches long for minimal kit impact

FAQ

Will autofocus and image stabilization work with this extender?

Yes. The built-in microcomputer maintains full communication between camera body, lens, and extender, so autofocus, image stabilization, and EXIF data all function normally.

What happens to aperture when I use the 2x extender?

The extender reduces the effective aperture by two stops. A 300mm f/2.8 becomes 600mm f/5.6; a 500mm f/4 becomes 1000mm f/8.

Which Canon lenses is this extender compatible with?

It's designed for Canon's L-series telephoto and zoom lenses. Check your specific lens documentation, but it generally works with Canon's premium tele primes and longer zooms.

How does the 2x III compare to the older 2x II extender?

The III generation improved optical coatings and lens placement to better control chromatic aberration, ghosting, and flare. It also added the fluorine coating for easier field maintenance.

Is this extender weather-sealed?

It's dustproof and weather-resistant, built to handle the same field conditions as L-series glass. The fluorine coating on exterior elements adds protection against moisture and fingerprints.

Will this extender fit in my camera bag?

At 2.1 inches long and 11.46 oz, it's compact enough to travel alongside your existing kit without taking significant space.