Cooking oil burns hotter than most fuels and reignites the moment it is disturbed, which is why a kitchen needs its own extinguisher. The wet chemical unit reacts with hot oil to form a soapy crust that seals the surface and cools it below its auto-ignition point.

Revere fits these in commercial kitchens, canteens and hotel back-of-house, usually alongside a fire blanket within arm’s reach of the range.