Does the outdoor car cover have grommets on the bottom edge so it can be bungee or tied down or locked on with a cover lock? In high wind areas covers without these often come partially or completely undone, sometimes never to be found again. Any details would be helpful. I am concerned about a $400 cover that could disappear while I am away from the car, and the description says nothing about grommets on the Tesla Store website, and I don't see any in the photos. I think this is the only cover that will really work for this car, but I wonder if modifications will be necessary to keep it from blowing away. Cheers.