Found this in a box of mixed parts and tools from an aviation workshop - they used to service Collins 618T HF radios, amongst others. Why would they have engraved matching serial numbers? Critical component? The parts were partly rusted together but separated quite easily with a dose of releasing fluid. I think it got droppped into box accidently, as it didn't match anything else there. Is it a fly press tool/die of some sort? Best wishes, Tom G4KWL.
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