... 3.Material: PVC,Sodium Acetate 4.non-toxic,reusable PVC magic gel pack for giftssize:11x11CMweight:100gs Simply flex the little ... metal disc, and they become hot instantly! Magic heat pad gives instant heat up to approximate 54°C ... active: Just click the metal piece inside the pad,the magic handwarmer will give instant heat up to approximate54°C-57 ...