Last month, I posted that I installed the Apache 2800 case from Harbor Freight. There were times that I thought it would be nice to have some extra storage, so I got the RosWheel 3 in 1 pannier bags. Ryan with Ebike Escape recommended these bags and talks about them in his latest video: https://youtu.be/lrYF4WU2vmo.
The bags are connected and are meant to strap to the back rack. I drilled and punched holes into the connecting fabric, got the grommet kit from Harbor Freight, and attached four grommets into the material where the rear rack screws holes are. Long story short, I can screw the four thumb screws down into the Apache case bottom, through the grommet holes, and into the rear rack screw holes.
The top bag can attach to the RosWheel fasteners and sit on top the the Apache case, though it does need to be upside down for more interior space. I tried it last night night for a grocery run and it worked great.
That looks great! We haven't gotten around to doing our 2021 list but the Roswheel panniers get a ton of use. We actually sold our green set to a friend and have a black set coming. Here they are if anyone is interested: https://amzn.to/3hlh1Cl