Gaskets/O-Rings for glass vial

What are you using to create the seals around tubes passing through the 20 mL vial caps? Do you have a link to them?

I have some extra 20 mL vial caps lying around, so I drilled 5 holes into one and want to add a fifth tube to connect to fourth pump (3 media, 1 waste). Let me know if you have any suggestions on ways to drill the holes or anything else that is relevant. Thanks!

We use these O-rings for the underneath cap and these grommets for the tubes.

Here’s a tip for installing the grommets through the drilled holes! Fitting Rubber Grommets (Blind Hole Nuts) - YouTube

Another thing: arranging 5 holes, with grommets, will be tight. I don’t know the best arrangement to fit them (4 holes fits okay, but you can see that 5 holes is not easy).