Cura-Heat Arthritis & Knee Refill 6 Heat Patches Cura-Heat Arthritis & Knee Pain Refills are air-activated heat packs designed for use in the Cura-Heat Arthritis & Knee Pain Wrap. Once inserted, they deliver deep and comforting heat for up to 8 hours and provide targeted, temporary relief to arthritis pain. With no need for preparation, just open the sachets and insert the heat packs into the wrap pockets. The comforting heat can help relieve the pain and aches associated with arthritis in the joint area by increasing blood circulation. Non-medical, fragrance-free, and with a thin, portable and discreet design, Cura-Heat Arthritis & Knee Pain provides a convenient way to manage your knee pain.