It generates heat quickly and effectively via a catalytic burner unit which usually lasts for 90 uses. This reusable hand warmer is environmentally friendly and is more effective than using a conventional warmer. Its compact profile means you can carry it around with you wherever your adventures take you.'Flameless' catalytic warmerBurn Time - 6 or 12 hours depending on fillBurner lifetime of 90 burns (assuming 12 hour burn)Protective fleece bagFilling cupLighter fluid not included