Grey squirrels, black squirrels and other medium to large size squirrels.

Grey squirrels will often roll off the feeder but not every time.
Sometimes grey squirrels will crawl and befuddle around on the Rollerfeeder, and sometimes they will hang from the bottom trying to figure out the design.
They will also crawl down the hanger side and try to reach around – the feeder housing turns and closes access to the seed trays when they attempt from the side.
They will often hang on the feeder and stick their nose through the grid but at an angle that prevents them from accessing the seed tray.
Rollerfeeder is guaranteed grey squirrel proof and other medium-large size squirrels.