Wild Bill's 12 Bird electric bird feeder opening

Some animal keeps pulling out the feeder openings to my Wild Bill's 12 station bird feeder. Most of the time I find them in the yard but sometimes I don't find them. I got fed up with putting duct tape over the openings that I couldn't find so I made these. They pop right in just like the original. It looks like many of the Wild Bill's bird feeders use the same kind of opening so this should fit the others that look like it.