Electronic
Viewfinder display of aperture, zoom and distance. (Distance display requires lens which supports distance information.)
Auto exposure.
Assignable function button.
Supports image stabilization (IS) lenses.
Power is supplied by camera body. No external power source is required.
Adapter firmware is user-upgradable through the built-in micro USB port.

Optical/mechanical
Extra-large, geared iris ring.
Secure breech-lock for locking the EF/EF-S mount lens solidly.
Flocking material is coated inside the opening to reduce internal reflection.