http://The cups are used by the 60th Aerial Port Squadron at Travis Air Force base in California because they can reheat coffee and tea on air refueling tankers in flight. But, because of the container’s design, the handle breaks easily whenever the cups are dropped.
http://www.foxnews.com/us/2018/09/26/air-force-squadron-spends-56000-on-metal-coffee-cups.html