Our mini heart heat pads are versatile, soft and all natural, made from 100% unbleached cotton and organic rye. Can be heated in your microwave or cooled in your freezer. They are unscented but smell amazing (thanks to organic rye!). Mini heat pads stay warm for about 30-40 minutes and can be reheated (or cooled) as often as you'd like. Materials: 100% Cotton (cotton & flannel heat pads) 100% Organic rye berries (USA grown) Measurements: 7 in x 5 in