I originally got the collar which comes with two of the ice pads.
But l like to load the collar with two ice pads
Since I live in Las Vegas I often want to use them a couple times a day - walking 🐕, riding 🚴♂️, out and about.
Sure makes a cool difference.
These are life savers. My husband is a cancer patient who is cold all the time and I run hot. It gets so hot in the house, and I just keep a stack of these in the freezer and swap them out when they melt down. It's enough to keep me somewhat comfortable.