It's liquid DFE(1,1,-difluoroethane) that's commonly sold in certain stores as
computer duster. It is used when neither dry
ice or liquid nitrogen is obtainable. It's usually used for science, to freeze things, or just for fun cooling thermometers, water, or some insects. The
computer duster can is used for dusting off the dust from computers using the DFE
gas. however, when turned upside-down, it provides a frostbite causing super-
cold liquid that's -25 degrees Celsius(-12 degrees Fahrenheit) or colder. It is sometimes(very very rarely) used to try to liquefy formaldehyde or other gases, but due to the toxicity of these gases, a gas mask is recommended. It can liquefy butane, a far less toxic, but highly flammable
gas. Getting Homeless man's liquid nitrogen on skin can be deadly, as frostbite can occur. It's a cryogenic liquid.
