This set of two extra-thick, heavy-duty and non-toxic nylon gel ice packs are ideal for keeping your lunches cooler for longer while out and about. With a sweat-proof design, they can be slotted into any lunch bag, box or cooler without soaking the contents with built up condensation. TIP: For best results, freeze cold packs overnight before use. They can also come in very handy after sports events or a heavy gym session, as they retain their flexibility when frozen and can be contoured to the shape of the body to reduce swelling and act as a fast and effective form of pain relief for aches, pains and sprains.