In the two point gripper system, gripper jaws engage a large diameter pipe. The system can be set up such that the grippers are attached to the dry dock and the pipe is driven into the ground with the top tied back to the pier or dolphins or the grippers can be attached to the pier or dolphins with the pipes attached to the dock.
The type of mooring makes it extremely easy to disengage the dock from its moorings and re-engage it back into the moorings.