What is the name of this stuff?

I am working on a project at my school, building a race car from scratch. Its much smaller than a GT40 weighing about 500lbs. I wanted to make use of the aluminum material i remember seeing my friend make his GT40 with. But i couldnt remember the name of the stuff. Its got like .015" honeycomb with .040" walls. Im sure you know what im talking about. So if you would, whats the stuff called?

Isn't it called aluminum honeycomb ?

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btw, sounds like a fun project /ubbthreads/images/graemlins/cool.gif

alright, I guess i just thought there was a name for it. actually hes on his 2nd GT40. Its a MK4 complete with 427 and all, built from scratch, and i have the privilage of driving it into the pits. Ya... You guys have awsome cars. /ubbthreads/images/graemlins/cool.gif