Yes, I use a derailleur with that integral with it (riveted on), for my folder with no conventional rear derailleur mount. Mine also has the punch mark at the slot radius, which puts a significant protrusion on the back side, to line up in horizontal dropouts to help keep from rotating. However, my bike has vertical dropouts so mounting with that would have caused the hanger to be laterally crooked, so I first ground that off on the backside to flush, spot of paint, then mounted on the bike under the axle nut, oriented by eye. The bolt and nut are also suppose to fit into a horizontal dropout, had to discard for mine, so when the wheel is off, the derailleur is just hanging in mid-air, not ideal, but it works. I tried using the bolt hole to one of the threaded rack eyelets, but it resulted in the claw being under only half the axle nut, I didn't like that asymmetrical loading, so removed the bolt and put the claw back fully under the axle nut.