... suits common life when weather turn cold,outdoor and work in open country,outdoor sport,go out for travel.it ... touch catalyst about ten second.One cup of oil can be work about 12 hours,two cups support to 24 hours ... go to school,travel,outdoor work,work on night,work in sea,guard,stand guard, mountaineering,go fishing,skee,etc. ... handy warmer into clothbag when use over. sell no.006 steel hand warmer