Bill, all of the tanks are convex.
The more that I think about this, the more it seems like there is a story here that needs to be told. I'm going to visit him next Saturday, and try to get more of the story from his perspective. Something along the lines of "what were you thinking putting a fire extinguisher tank on your back?" Since he worked for the Santa Monica Police Department, I was told that he dove off the Santa Monica pier for forensics, looking for weapons and other things related to crimes.
The more that I think about this, the more it seems like there is a story here that needs to be told. I'm going to visit him next Saturday, and try to get more of the story from his perspective. Something along the lines of "what were you thinking putting a fire extinguisher tank on your back?" Since he worked for the Santa Monica Police Department, I was told that he dove off the Santa Monica pier for forensics, looking for weapons and other things related to crimes.