This Reusable First Aid Ice Bag and Heat Pack for Pain Relief is made of heavy-duty waterproof fabric that keeps the ice-bag cold and dry. Ice-bag features an easy to fill large opening with plastic cap to keep ice secure and melt water inside the bag. Use this product after an injury to reduce swelling and decrease pain. Relieve pain and discomfort from bruises muscle aches swelling headaches and more. Ice decreases blood flow to the injured tissue and reduces inflammation. Cold therapy generally works best when used for 20-30 minutes every 3-4 hours or until swelling goes away. Simply fill the ice-bag with ice close lid and apply to the desired location. The Relief Pack is refillable and reusable to use at home work or on the go. This multi function bag can be used for hot therapy as well. Simply fill the hot water and use it without worry as its completely water proof. The top shape of the bags helps in using the bag more efficiently compared to other hot water bottles/bags. Reusable First Aid Ice Bag Instant Pain Reliever Hot and Cold Pack Reusable First Aid Ice Bag and Heat Pack for Pain Relief is made of heavy-duty waterproof fabric that keeps the ice-bag cold and dry. Ice-bag features an easy to fill large opening with plastic cap to keep ice secure and melt water inside the bag. Use this product after an injury to reduce swelling and decrease pain. Relieve pain and discomfort from bruises muscle aches swelling headaches and more. Ice decreases blood flow to the injured tissue and reduces inflammation. Cold therapy generally works best when used for 20-30 minutes every 3-4 hours or until swelling goes away. Simply fill the ice-bag with ice close lid and apply to the desired location Fast Relief: cold pack is suitable for use of cold therapy to help reduce slight scratches bruises muscle pain sprays and strains and swelling. It is recommended to help relieve pain reduce swelling and speed recovery.