Canon EF or EF-S Lens to Micro 4/3 Body
Third Party EF or APS-C EF to Micro 4/3
Supports Electronic Communication
Enables Use of Lens Autofocus
Enables Lens Aperture and Stabilization
Adapter Interior Minimizes Reflections
Locking Mechanism to Secure Lens
Push-Button Lens Release
Brass Mounting Rings
Detachable Tripod Foot

Features and Benefits

Electronic

Autofocus
Can be powered either by camera body or by third-party external 5V power source (not included)
Iris/aperture controlled by the camera body
Smooth iris support with the latest Canon (2009+), Tamron (SP series 2013+) and Sigma (2016+) lenses
Image stabilization (IS) lens support
Support for cameras with in-body image stabilization (IBIS), including Panasonic GX7, GX8, GX80/85 and Olympus cameras
Electronic manual focusing (e.g. EF 85/1.2L II and discontinued EF 50/1.0L)
EXIF (focal length, aperture, zoom range)
Distance and zoom display on camcorders (requires lenses supporting distance information)
Cinema EOS lens support (CN-E 18-80mm T4.4 L), including AF (requires external 5V power through micro USB port), auto iris and servo zoom

Other

Detachable tripod foot compatible with Arca Swiss, Markins and Photo Clam ball heads.
The opening is flocked with felt material to reduce internal reflection.
Compatible with all MFT mount cameras, including GH4, OM-D, Blackmagic Cinema Camera, Blackmagic Pocket Cinema Camera and JVC GY-LS300.
Supports EF-S lenses.

LIMITATIONS

No video AF for Olympus
AF may not work if the maximum aperture of the lens plus any EF Extender or other teleconverter attached is smaller than f/8.
AFC (continuous AF) and AFF (flexible AF) modes are not supported, except on Olympus OM-D E-M1.
Panasonic video AF may hunt more than a native lens or have unsatisfactory performance.
Some Tamron lenses may have unsatisfactory AF accuracy.
No support for Focus Stacking and Focus Bracketing on Olympus.
On Olympus, other than E-M1, you may move the single AF point among any of the 81, but you may not multi-point AF. There is no restriction on E-M1 and Panasonic.
Very early Olympus models (e.g. E-PL1) have no autofocus support.
EF-mount lenses are not silent but may make audible click noises during autofocus operation and iris changes which may be picked up by the built-in microphone of the camera. An external microphone is recommended for video.
Use of Canon Cinema lenses such as CN-E 18-80mm T4.4 L IS KAS S for still photography is not supported.
Iris changes are in 1/8 stop steps which may be noticeable in video recordings. Programmed exposure mode and shutter priority exposure mode should not be used for video. This limitation does not apply to Cinema EOS lenses which permit fine resolution iris control, such as CN-E 18-80mm T4.4 L IS KAS S.
No support for in-camera correction such as peripheral shading, CA and distortion

Autofocus with an Optimum Balance of Accuracy, Speed, Consistency and Reliability

Autofocus is supported subject to certain limitations (see table below for details). We are pleased to report that Panasonic Micro Four Thirds camera bodies are capable of autofocusing fast (large maximum aperture) lenses accurately. Although our first and foremost priority is accuracy, we are able to make great strides in autofocus speed as well.