Usage:1. Use as the first time : hold the bag with one hand while press the hot button disc several times inside the bag with the pollex and foxefinger of your another hand.The liquid shall turn to solid an release heat soon. 2.do as the second time usage if the bag is solidYou can press the bag face to make the bag flat and the heat can spread easily. .Put the bag on the face where you need when its hot. 3.Use as the second or more times The bag shall turn cold after you make use of it for about 42minutes.You should heat it in the boiled water for 3 minutes with cotton cloth or towel enwrapped. You can use it again after it turn to liquid.Be care of scald. Of course, we can put it into microwave (in a container completely with water would be better), heating it at mudium heat for 40 seconds. 4. The liquid should turn cool and you can use it according to the step of the first use.Heat therapy or to warm the body, Cold therapy or to cool the body, Can stay hot or cold for around 30 mins, No spill out... Application: COLD Store in the freezer so that the pack is ready to use in case of injury. Approximately 1 hour is required to freeze gel. IDEAL TO USE FOR: Reducing swelling Toothache Temporary relief of headache Reducing fevers CAUTION: Whether used HOT or COLD, it is advisable to check that the temperature is not too extreme against the skin. It is recommended that the gel pack is wrapped in cloth before applying to skin.Application: HOT MICROWAVE: Place gel pack into microwave for approximately 30 second (if the gel pack is at room temperature) or 1 minute(if the gel pack is frozen) on high power. After this time, check that the correct temperature has been reached. If not, further exposure should be in 10 seconds bursts.Times are based on a 600W microwave: adjust heating times accordingly to suit the power of your microwave.HOT WATER: Bring water to boil, remove from the heat, and immerse the gel pack for approximately 4-10 minutes. After 4 minutes, check every 1 minutes to see if the correct temperature has been reached. Ideal to use for temporary relief of muscle aches and pains, back pain. 1) used in long distance refrigerated transport 2) daily life: cold preservation and electricity saving 3) medical treatment: defrevesce , diminishing inflammation and easy pains , hemostasis , physical therapy and skin care . 4) sports: accident injury , wrench and in training and matches We can supply cold and hot packs, instant ice packs,... Hot and Cold Gel Pack(gel ice pack,hot and cold compress,cold compress) Characteristics: 1. This product is made up of high polymeric compound and diversified biological elements. It has already passed FDA,CE,MSDS,and proved that there is no side effect to human body. The scientific prescription makes the bag elastic and it can remain soft for a long time in the minus 20 centi-degrees environment. So it is locally named Ice-free Bag. 2. It can be bent arbitrarily according to the applied place when it is used, press close to the joints and muscles to make the treatment more effective. 3. It can adapt unlimited times of alternately cold or hot use after pre-cooling or pre-heating treatments. Indications: Cold compress:headache, fever, toothache, sunstroke, scald, muscle scuffing, sprain, trauma haemostasis, beauty etc. Hot compress:arthritis, rheumatism, menorrhalgia, stomach trouble, cervical vertebra trouble, sciatica, and strain of lumbar muscles etc. Sinusitis and menstrual cramps.Contents: Trimethylene glycol, CMC, Water Precaution: 1.Don't puncture or abrade the bag with spiculate stick. 2.Don't press the button if the bag is releasing heat. 3.Turn to a doctor when necessary 4.Not for eat and make it away from childrenContents: Sodium acetate ,water Non-tonxic,non-caustic.If you are interested in it ,please feel free to let me know. Have a nice day.