There is nothing on the box, on the label or on the enclosure that indicates the weather rating.
I would expect it on the product spec label on top of the box, even if it was nowhere else.
The only place I could find the rating was in the catalog, in the chart referenced above that has the model numbers for each timer model. I don't carry one of those catalogs, does anyone else?
My big problem is these are in a "retail" box, not something you would expect at a supply house and they are marketed directly to consumers at the big box stores.
If the customer read anything available on the box they would assume this was OK outside (3R) and wouldn't ever be told any different until a "code geek" like me told them
I am still not sure I convinced the guy and I know he used it. I did talk him into going around the corner under cover with it so it was "damp" and not "wet" but I bet it is rusted out in a couple years.
I do see a lot of these outside and I have replaced more than a few that were falling apart.