If I have my Ubiquiti UAP-AC-HD set for ch 36, 40, 44, or 48 (5GHz, 80MHz channel) then the EA-AC87 can't see it, if I set it to use one of the high channels, 149, 153, 157, or 161 then the EA-AC87 can see it.
The upper channels are much more noisy in my location so I get a cleaner signal with the lower channels.
The e-bay listing for the EA-AC87 said "From USA" though the box it came in had kanji and I'm not fluent in those languages so I can't say which language it is.
The Web UI is in English though.
Also the unit does have an FCC logo on the bottom.
The plan is/was to use the EA-AC87 as a media bridge so that devices with lesser wifi implementations could simply be hard wired to the bridge.