Cura heat back pain direct to skin max size 2 heat packs cura heat back pain direct to skin max size can be applied directly to the skin for those who prefer direct skin application heat therapy the hinged extra large heat patches deliver 8 hours of soothing heat and provide targeted temporary warming relief from muscular and joint aches and pains just open the sachet unfold the heat patch and apply directly to the skin over the painful area where the heat will increase blood circulatio