Im not metallurgist, But i was surprised as heck when i tried sticking some rare earth magnets to the light and they didn't stick. I could even feel them have some pull threw the light being attracted to the 18650 cell as when i took it out it had no pull what so ever.
so are there non-magnetic stainless steels i don't know about, Or is this light a heavy aluminum alloy of some sort?
Nope stainless is not magnetic never was nothing strange to report there.
Well ill be a monkeys step-son! I didnt know that.
Would you believe they let me drive cars too!
Ok thats my last dumb question of the day, Thanks for clearing that up.
I work in a biotech plant and everything except the floor is made out of stainless so I kind of figured it out after a while.
I became aware of that a few years ago - it surprised me at the time.
The 300 series alloys (or austenitic) stainless steel are not magnetic because of the nickel content. Other types with no nickel in the alloy are magnetic (ferritic and martensitic stainless)
It is a good thing that it is a non magnetic type as they are the most corrosion resistant. I don't see a rusty flashlight being a good thing...
Yes, there are some type of SS which are very slightly magnetic, and as you'd have guessed not totally corrosion resistant esp if you put it out in the open. Some should not even be technically called SS (cut-cost).
I have ss knives and forks( for eating my dinner) they are all magnetic?
They have no corrosion at all, had they for over 20 years
Friend, ever heard of plating? 
Yes you are right.
Is it not cheaper to plate flashlight than making them 100% SS?
It depends, for flashlights there are batche variations, there is no telling when the manufacturer would cut cost. I know that my Ultrafire C3 SS is definitely full stainless steel. It is way too solid and heavy. When empty, it weighs more than my Xeno E03 with a 14500.
You cannot plate stainless steel onto carbon steel, his knifes are stainless and magnet because there are different types of stainless steel and several are magnetic. My kitcken sink is stainless steel AND magnetic but it doesn't rust and it's not plated as stainless steel....can't be done that way.
Also IF it was possible, he wouldn't be able to sharpen his knifes w/o the "plating" coming off and then rusting.
So Yes friend we've heard of plating, but it doesn't apply here.
The G6 is stainless steel, not plated brass. Some stainless steels are magnetic, some are not (tested with a magnet and none of my stainless lights are attracted to it, while all of my stainless knives are).
its a generic term seems they range the gamut for nonmagnetic to magnetic
It is important to understand that stainless steel is not a pure magnetic metal. In fact, stainless steel is really a collective name for a steel alloy that is mixed with other metals in order to give it the properties that make the metal compound so desirable. For instance, the typical stainless steel contains just over ten percent of chromium.
In fact, it is the presence of the chromium that provides stainless steel with the ability to repel permanent stains and keep looking fresh and clean over long periods of time. The chromium essentially creates a protective layer on the alloy that prevents rusting and makes the metal resistant to any real damage. Any scratches to the surface are simply filled in by this protective layer, making it possible to prevent corrosion to occur. It is the introduction of chromium into the mix that we refer to as stainless steel that makes it possible for the alloy to exhibit magnetic properties.
I want a "food grade" flashlight now! : )
And lets not forget its name "stain-less", not "stain-proof". (several definitions, usually defined as a steel alloy with 13-14% or more chromium, although high carbon stainless steels still has a tendency to rust due to the formation of chromium carbides, other elements are often added to help prevent this loss of stainless-ness)
Above fished from memory, best served with a grain of salt.
Hey be careful with that grain of salt, it's corrosive :)