The heat patches activate with air and adhere to the inside of your clothing thus minimizing the irritation many people experience when using direct-to-skin adhesive products. Keep this value pack handy for the entire family, or stock up to ensure you will have soothing pain relief ready at your fingertips when you need it most. 10 Hours of heat per patch. Ideal for neck, back, shoulders, hips, etc. Specifications: - Height: 6.5" - Width: 5" - Depth: .50" - Weight: 1 oz.