These are customized motors. High power, precise, 28P with built in encoders. Their final shape and construction will be different than what you can see on prototype unit photos.
Here you can see how to mount IMUs.
There is also one advantage that you can't see on the photos. Camera IMU cable can be protected by a rubber ring (in the place it outs of the housing) and snake skin. All those accessories are included in every set.