A safe way to keep your body warm as well as relieving stress, muscle and joint pain, the Heatbag from Ostrichpillow is the perfect hot or cold comfort. With a recycled memory foam cover lined in a soft jersey fabric, hugging the Heatbag can help to relieve stress or pain; with a unique composition of eight layers and two differentiated sides, it ensures that the heat is released slowly and focused on the desired spot, preventing you from getting burnt by cold or heat. * Clay filling is a natural and safe heat source **How To Use:** Place the clay bag in the microwave and heat it at 1000W for 35 seconds. For cold effect, leave the clay bag in the freezer for at least 1 hour.