Plastic explosives was used for decades prior to the War as a mining tool, and is still useful for removing inconvenient nature. Like its more primitive cousin, dynamite, plastic explosives is both a tool and a weapon. Typically made from a powerful explosive like Semtex or RDX, with a plasticizer, they are a very stable and malleable compound. Plastic explosives can be rigged to explode with either remote or timer detonators, and can be detonated with other high explosives.
A package of plastic explosives in an off white wrapper, with a yellow and red label stating "C-4 Caution High Explosive" that appeared in Fallout Tactics. Plastic explosives was cut from Fallout: Brotherhood of Steel at some point during development.