Rear rack bags for RadExpand 5

[coldweather]

Trying to get the best fit accessories for my new e-bike:
Does anyone have a good recommendation for a rear rack bag (trunk)?  I've already picked up an insulated bag with velcro straps that are too short and won't tie down to the rack, so I ended up using bungee cords.  Also, what accessories will mount using the threaded holes on this rear rack?

Thanks.

[JimL]

This one fits, Lixada on Amazon, about $22 right now.

https://amzn.to/3XTvPvX

[coldweather]

Thanks for this suggestion and link.  We'll give it a try.

[Charlieparsons67]

I have had a hard time finding one.  I am currently using a bag i got from amazon it has velcro tie downs.  I had to buy more velcro stripes and get creative but it works good now.  Rad just came out with hardshell boxes that i belive will fit on the rack and are compatible but its kinda pricey. The top box is like 159 or something and the hardshell panier is 199. My advice is to get creative and make your own style.

[John Rose]

My DIY proposal:
Once you fabricate and install a simple pair of shields (to keep stuff off the rear of the frame and derailleur) out of a sheet of lexan or clear acrylic, I'm thinking you could just flop two fabric shopping bags over the rack, like panniers. Fasten the bag handles to the opposite sides of the rack with carabiners or bit snaps. Should be fine for toting groceries.

That being said, I did just order a Rad Saddle Bag (with $10 discount) for little stuff like the bike lock, cable, and tool kit.

[edit - Oops.  I forgot about the possibility of the bags hitting my heels as I pedal. Clearly I have to try it out first, and then proceed with the mods to keep them more to the rear.]

[RadBob]

We ordered the adapter plate for the Topeak bag that just slides and locks in place.
The reason is we couldn?t get our folded Expand 5 bikes into our Equinox with any type of bag on the rear rack. 
We plan on carrying a spare battery with each bike and although the Topeak system was pricey, I think the convenience will outweigh the price.