Fast Acting & Long Lasting--Take effects in 5 minutes, last up to 8 hours,back patch offers fast, continuous soothing for back aches. Our natural patches can also help ease joint stiffness, sports injuries, muscle soreness, strains and sprains. Natural Herbal Ingredients--All ingredients atback patches are natural without any side effects, artemisia, menthol, capsaicin, ginger, which provide targeted & deep penetrating heat to the affected area, promote blood flow & oxygen to loosen muscles and reduce soreness. Sensitive skin may feel more strongly, please tear off if you feel discomfort or unacceptable. Multiple Comfortable--With rounded corners and flexible fabrics, patches for back flexes with your movements without interfering with daily life. The ergonomic design allows our back patch to fit more closely to the spine and will not fall off easily, ensuring full relaxing in back muscles. Easy To Use-- back heat patches simply clean the affected skin with warm water, remove the protective film and stick the warming herbal patch on your affected area. Use one during the day and one before bed for better effects.