Lux meter: FX-200 illuminometer

Does anyone have experience or opinion about the Watt Stopper FX-200, such as found here for not much money? https://www.ebay.com/itm/193480718130

It looks like the same case design used with old Fluke 8060A multimeters, but that could just be a knock-off.

Anybody have an operating manual? Came up empty on the WS website.