I have only the one of each which makes it hard to determine which is off.
I know where the flash hider came from (762mmfirearms). As far as I can tell the bayonet is authentic but I can't see any markings on the blade. The handle is black plastic held on with two flat head Philips head machine screws that engage hex nuts in recesses. The sheath is green plastic with a green web belt loop and old style clip. The metal at the top of the sheath is marked "U.S. M8A1 Made In Germany".
It is not a huge issue because I have no need to affix the bayonet, just something that seems a bit odd if the flash hider is supposed to be made to the original drawing. But of course I have no way of actually checking that either...
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