Oxygen Wrench

I was asked to print an oxygen wrench and could only find one on the internet (http://www.thingiverse.com/thing:897996/), but I didn't like the design. I think it's a marvelous looking object, but I have my doubts about how well it will hold up over time. So I whipped up some test objects for dimensioning, then added a quick handle. v2 will be more refined.

Update 8-2-15: I had too much time to play yesterday, and went through three more iterations. I tried a number of different designs, bu