The cushion is heated in the microwave or in boiling water. It stays warm for 2-4 hours. The cushion is reusable. The cushion can also be placed in the freezer for a cooling effect.
The user places the heating pad on his lap when he is cold. In recent times he has used a homemade linen bag filled with peas that has the same function and that can also be heated in the microwave.
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