"gel ice pack"
I always order gel ice packs with my vaccines. Occasionally they are punctured, but if you put them in a zip-lock sandwich bag you can use them over and over again in a cooler or other use needing a cold pack. Use 2 day shipping with these packs, and they will still be cold on arrival.
Both packs in my order were punctured and leaking. Barely colder than room temp. Will not waste the money again, will pay extra for overnight shipping.
These are great for coolers, picnics, or injuries at horse shows for people and horses too. In Florida they are really nice to hold when it's 90+ degrees and you think you are going to melt.