Model Number: Reusable Heat Pack-D19F Brand Name: J, J-jiaxing Key Specifications/Special Features: Materials: PE, nylon + PVC/sodium acetate/water or otherIdeal for outdoor sportsStays warm for hours and is reusableOne color imprint onlyDiameter: 4 inchesColor: whiteApplications: exercise, fitness, outdoors, sports, travelVarious heat packs are availableCustomized colors and designs are accepted, such as printing your logos for promotionsPacking: inner 1 piece/carton