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this is correct. What happens is some suppliers set up "ghost companies" to get OEM pricing on components, there may or may not be frames from 1994 in a factory somewhere for these parts to go on, but either way, you are getting genuine shimano in a plastic bag with no documentation or packaging. I bought a lot of Di2 rear Mechs like this as it was only affordable way to replace my broken ones. I never had to warranty one, but I'd check with the seller that you get warranty. I also bought a few sets of MT520 4...