4.9 MB (989.6 KB compressed)
1439 x 1181 pixels
12.2 x 9.9 cm ⏐ 4.8 x 3.9 in (300dpi)
CHARLES D. WINTERS / SCIENCE SOURCE / SCIENCE PHOTO LIBRARY CHARLES D. WINTERS / SCIENCE SOURCE / SCIENCE PHOTO LIBRARY
These are single use packs to warm hands and to apply cold to injured areas. Air activated hand warmers contain cellulose, iron, water, activated carbon, vermiculite (water reservoir) and salt and produce heat from the exothermic oxidation of iron when exposed to air. Instant cold packs consists of two bags, one containing water, inside a bag containing ammonium nitrate, calcium ammonium nitrate or urea. When the inner bag of water is broken by squeezing the package, it is allowed to dissolve the solid in an endothermic reaction.
Model release not required. Property release not required.