If you look at his videos you will see that the only metal on his bunkers are the outside shell. The inside is all built with cheap prefab mobile home parts and walls. Not only are these horrible for your protection they will easily wear down over time. If your bunker floods you can not recover any of the inside pieces of mobile home prefab, not to mention that it is an enormous fire hazard! Stay away from these cheap mobile home bunkers. Not only are the welds horrible which you can see in every video he posts on his on channel but the insides are trash!