If you’re talking about a Keurig know they’re not made for Keurig. They work with my machine that uses Nespresso capsules. It is called innisia.
Nespresso machines take two different size capsules one looks like a little upside down cup while the other is a little bigger around and sort of flat compared to tall. The smaller capsules are easier to fine so if you decide to get this kind of coffee maker be sure to check what size capsules it uses. Where is smaller than a Keurig capsule but it is amazing how much intense coffee comes out of it