Based on The Soviet ''Molotov Incendiary Device'' (also known as ''The Cocktail'') – The US M1 ''Frangible'' was a glass container (bottle), which carried a variety of caustic or flammable substances. Unlike using a makeshift ignition system (rag or cloth soaked in a flammable substance), to which was lit with flame as the primary ignition source – The US Frangible featured a small ignition (timed) fusing system. Designed for use by Partisan (Freedom Fighters in Occupied Enemy Territory), Commando Forces nd occasionally Mainline Troops – The Frangible was seen as a cheap and effective improvised explosive device.
Some versions could contain specialized substances. Phosphorus, Thickened Gasoline (an early form of Napalm) – were just two forms of liquids used. Even basic types of Chemical Agents such as Mustard and OC Agents were adopted. They were used against structures, Armored Vehicles and Personnel. Specialized training was given to selected personnel for their storage and deployment. First deployed in 1942, they were in used until the end of The War.