I'm not sure if this exist?

[CatLady]

Welcome! Here’s some info that may help you:

Filling your own pens

I’ve been filling my own pens for a while. Why? Not all the disposable pens are refillable Re-filling from a vial is cheaper than buying disposable pens. You can fill them with any amount you want. Rather than having 300 ml sitting outside for months (that’s how long it would take me to get through some of the basal ones), or always having to go into the refrigerator to get one out, I can just fill it with a week’s supply at a time. Only one week’s worth stays outside, the rest of it stays in…