now I get to fool around with these things again. If you think a K5 is heavy try putting one os these things on the scale. The armor alone is 4000lbs. Opening the 300lb doors and looking through the aquarium glass is something else. 1/2" and 3/4" of steel to protect the occupants Not the best on the back but I would feel pretty safe in it. And one little creature comfort. A/C I see that as the first thing that they take out. Sitting in a steel can tends to make you a little hot. And just one more of my baby the day before she left.