(How) can a pannier rack mount on the Specialized Diverge Elite E5? If I look at the images of the Specialized Diverge Elite E5 I see on the underside of the seat stay 2 black pieces that look like rack mounts. ![The bike]( However, I've only seen them on the upper side of the seat stay. Are they pannier rack mounts or something else? If they are rack mount, how can I connect a rack to them? Is there a reason to add those to the bottom? Does that somehow improve something?

They are fender mounts. A bridge is connected to those mounts, and an L-bracket connects the bridge to the fender.

As for pannier rack, there are fenders that carry lightweight panniers, such as Hebie Wingee. If you want to carry more than 8 kg per side, then you need a real pannier rack. It needs mounts at the bottom and at the top of the seat stays. Usually those under-the-seatstay mounting holes don't work because regular pannier racks are intended to be mounted to eyelets that have the screw holes at the sides of the seatstay. Theoretically you could fabricate custom mounts for those under-the-seatstay holes, though.