... to use,can reach 43 C. long tiem hot-last about 40 minutes 2.Non-toxic,non- ... caustic.disposable.Instant Hot Pack Function:1.Easy to use,can reach ... .Shake to mix contents.Application:1.This instant hot pack can release heat within 5 seconds,conveniene ... to reduce body temperature and relieves pain and swelling.Application range: (1) Bruises, muscle aches and sprains, toothache, ...