Aqua bead gel therapy pack is microwave and freezer safe. Keep stored in refrigerator or freezer for cold use. Instructions printed on backside of item are general hot/ cold pack therapy guidelines. Aqua Pearl is reusable, pliable and non-toxic. Safety tested for CPSIA, FDA and TRA (Toxicological Risk Assessment).A square version of our "Original" Aqua Pearls (WHF-HC11),Simply microwave for warm therapy or freeze for cold therapy,Double Safety Tested: CPSIA, FDA, and TRA (Toxicological Risk Assessment),Safety reports for Pearl beads are available upon request,Reusable and easily cleaned with mild soap and water,Available in a variety of shapes, colors and themes.