Review on Polar Tech Leakproof Viscous Refrigerant by Stephen Parkell

This is our second purchase. I sometimes ship chocolate across the country and this keeps the contents cool enough to prevent melting. And then they are reusable! Pretty cool. Our main uses for it are lunches and trips to the parks. Drop them and don't worry about the ice melting. So inexpensive that you can throw it away if you accidentally puncture it, scratch it by dropping it, or your child chews it without your knowledge. I think the denseness description is correct. This is the 2 millionth plastic. People may not like to hear it, but personal responsibility! It's not airtight if you drive a nail into it, it's airtight if you use it multiple times for its intended purpose. I'd used up a couple I've been using for over a year and a couple that came back at lunchtime, obviously after one try. Most are somewhere in between. I have a few that live in their own ziploc bag for added protection as they are fork packed. Who knows what happened to that in my 6 year old son's snack bag? I'm not opening a federal investigation into this.