Tired of burning your tongue on coffee only to have it get cold a few minutes later? Your coffee will be ready to drink faster and will stay in the perfect temperature range longer. Each polished stainless steel shell is filled with an advanced phase change material that melts at 140°F. Put them in your coffee and they absorb heat when it is too hot, storing that energy inside. When your coffee reaches the perfect temperature this stored heat is released to keep it there longer. The 5-Pack works with up to 20 oz of coffee, one bean per 4 oz.