I suspect that's because they don't have a final model yet. Notice that this page states: Actual size and weight of the device may vary due to configuration and

I suspect that's because they don't have a final model yet. Notice that this page states: Actual size and weight of the device may vary due to configuration and manufacturing process. They announce what they know will be there in the final product. When they have the full final spec, they will show it to us.