Dunno what it's made of, but it's got more chainring bolts than is traditional.
It's a chainline adapter, like the one Fibrelyte made for Cliff Voller, which you posted in the Fixed TT bikes thread
Ya know I did wonder if it was something like that, but I thought the BCDs weren't different enough.
@umop3pisdn started
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It's a chainline adapter, like the one Fibrelyte made for Cliff Voller, which you posted in the Fixed TT bikes thread