I love the C200 feeder and bought these ice packs in case I forget to freeze a set. They work well, for the feeder etc, and make feeding wet food healthy and easy for my cats. My only caveat to these ice packs is that they tend to bubble or get weird bumps in them that preven them from laying flat under the food dishes. I have tried completely thawing and refreezing, but for whatever reason they freeze into funny shapes. They still do the job they are designed to do.