The M202 FLASH ("Flame Assault Shoulder") is an American rocket launcher manufactured by Northrop Corporation, designed to replace the World War II–vintage flamethrowers (such as the M1 and the M2) that remained the military's standard incendiary devices well into the 1980s. The XM202 prototype launcher was tested in the Vietnam War, as part of the XM191 system.
The M202A1 features four tubes that can load 66 mm incendiary rockets. The M-74 rockets are equipped with M235 warheads, containing approximately 1.34 pounds (610 g) of an incendiary agent. The substance, often mistaken for napalm, is in fact TPA (thickened pyrophoric agent).
TPA is triethylaluminum (TEA) thickened with polyisobutylene, in the presence of n-hexane, preventing spontaneous combustion after the warhead rupture. (TEA), an organometallic compound, is pyrophoric and burns spontaneously at temperatures of 1600 °C (2912 °F) when exposed to air. It burns "white hot" because of the aluminum, much hotter than gasoline or napalm. The light and heat emission is very intense and can produce skin burns from some (close) distance without direct contact with the flame, by thermal radiation alone.