Blue Opus 88 eyedropper with a #5 sized F nib. I'm not sure what the model is, since it seems to be discontinued, but I've had it for a long time. It has mostly been sitting in a storage/display box after the first use.

It has been filled once and there is a bit of a small ink ring in the barrel near the plunger threads, which can probably be more thoroughly cleaned. The threads and o-rings have had silicone lube on them to help with sealing, and the pen itself is clean and functional. I don't have any of the original box/papers or eyedropper (always syringe filled), but I will ship it in a Franklin Christoph pen sleeve.

Editing to add: I found the model! it's the opus88 picnic

Asking $70 OBO PP G&S shipped within the continental US.

https://imgur.com/a/YzsliHz