Keep your hands warm this winter with Lifesystems hand warmers. Handy and reusable with an activation time that lasts 90 minutes, emitting heat up to a whopping 54 °C. To \'reset\' the crystallised pad to its original gel form, just add the pads to a pan of boiling water and allow to simmer until the crystals have completely dissolved. Allow to cool totally before handling. To activate, pop the metal disk and massage the gel pad as the gel begins to crystallise, instantly releasing heat. The perfect companion whether it\'s a walk to work or a hike up Snowdon, they conveniently tuck inside gloves and coat pockets, keeping your hands warm on those icy days.