Masterbuilt Hitch-Haul Cargo Bag, Black 26996

My local Walmart had this on clearance so I picked it up when I bought the hitch haul cargo carrier. As mentioned, the bag is about a foot shorter in length than the actual carrier. The outside of the box does say weather resistant, and the warning inside the box does say it is not water proof. The entire bag is lined with some sort of vinyl, and should give good protection in a decent rain. The top zipper zips on three sides, the rear of the bag has a zipper to let it expand even deeper. All zippers have ~2" zipper flap that is sealed down with strips of Velcro. Interestingly, the attachment of this bag is a bit odd as it isn't really intuitive as to how it should secure to the carrier, but it does work.

Beware: this requires specific holes to match up for clips to attach to mount it. I think it would be fine if you have the compatible carrier rack from the same brand, but this unique design makes it impossible for someone like me to use it. (I will be taking mine back with some frustration that it doesn't mention this compatibility limitation on the box. For me, I'm going to try this more universal model that is waterproof appears to be higher-quality overall (might be a tiny bit smaller, but I need it to fit my hitch carrier rack): http://www.walmart.com/ip/ROLA-59102-Rola-Expandable-Cargo-Bag-9.-5-To-11.-5-Cubic-Ft.-11.-60-x-9.-20-x-5.-70-inch/35535383