Does 408.8.a still apply?
We are still under the '05 book here believe it or not, so the flip covers should be okay.
There is a graphic on the web table 3.8, just can't pull it down.
Attended / non attended is the key here.
So a cover for a water feature continually running vs a leaf blower, drill etc.
2) Other Receptacles. All other receptacles installed in a wet location shall comply with (B)(2)(a) or (B)(2)(b).
(a) A receptacle installed in a wet location, where the product intended to be plugged into it is not attended while in use, shall have an enclosure that is weatherproof with the attachment plug cap inserted or removed. (Exhibit A)
(b) A receptacle installed in a wet location where the product intended to be plugged into it will be attended while in use (e.g., portable tools) shall have an enclosure that is weatherproof when the attachment plug is removed. (Exhibit B)