Reuseable maybe
These were fine, I have about four of them but two of them leaked eventually (after 2-3 months of use). I only use them for cooling (return to freezer after use).  But I covered the “leakers” with a ziplock bag and they work fine that way (for now).<br /><br />As far as using them warm, I’d hate to see what would happen if I put them in the microwave.
Rating: 3 stars