The 2189 plate is compatible with the following camera bodies:
Acratech quick release plates are compatible with all Arca Swiss type clamps. The camera specific lip prevents rotation on your camera body.
Posted by Unknown on 9th Oct 2016
This plate fits perfectly on the A7RII and the lip prevents the camera from twisting on the plate in portrait mode - a problem with generic plates. Great product - if you're going to use a tripod it's worth getting a plate like this that is designed to fit your camera. Why skimp?