I see what you're saying. I use generic toner cartridges and they do have the same hole on the left side, but looking inside, it doesn't seem like anything is missing from there at all. Maybe it's a piece that was left over from a previous toner that I just happened to discover.Hi PD! I'd say you were ambitious, and trying to clear up a problem. I looked inside myL2360DW and saw nothing that looked like that. However, I looked at the toner cartridge and saw something that resembled a part of what you show here, but since it was inside the toner cartridge I could not see the whole thing. If it is the same piece, it's hard to imagine how it would've migrated out of the toner cartridge. I am attaching an image, which may or may not make sense. If we have the same toner cartridge (TN-660), you will see this on the left side of the unit when you remove it from the drum unit. Good luck!