I bought them on Amazon. The brand is Newgo. I got the slippers and the mittens with wrap around strap.

https://www.amazon.com/NEWGO-Slippers-Neuropathy-Chemotherapy-Diabetes/dp/B09NY1BLTN

https://www.amazon.com/NEWGO%C2%AEIce-Arthritis-Injuries-Microwavable-Freezable/dp/B086TT46FM