Pens for insert shelves not included?

Hello,

do you have to buy them yourself or are they included with a cabinet?
Somehow I feel like something is missing, or rather, what kind do you need?

No, they are included - what kind of cabinet/shelf is it? Depending on that, the pins are packed with the shelves (e.g. Faktum), included with the screws, or clipped into the holding rails of the boards (e.g. Ivar).
Regards,
IKEA-Fan

I am already so balaballa from putting it together that I threw away the little red bag that came with it. I've seen that with other shelves. My fault.

But sometimes you don't immediately understand something from a package :)