It may seem a nuisance, but the User's Manual is a poor scan of a printed manual..
I don't know any serious manufacturer that does not have the source documentation of their own product (thus generating a true PDF).
Also, the page says Manufactured in Korea by SMTECH. That is probably the ODM.
As mentioned by Lightages, if you are looking for a data logger and will never use this in high voltages that could work. However, In my opinion I would probably save a bit more and bet in something from a more reputable brand (EX540 from Extech, for example).