That's an Ibera thermos. http://www.amazon.com/Ibera-Co-Ltd-S.../dp/B0012Q9TO4

It has its own mounting hardware (that the handle slides in), but I am not using it. That's a normal bottle cage on my bike. It fits well in a normal bottle cage. It works best with the kind of cage with no front because then the handle is straight out, but you can turn it sideways and it fits fine in most basic wire cages.