C4 is made up of explosives, plastic binder, plasticizer and, usually, marker or odorizing taggant chemicals such as 2,3-dimethyl-2,3-dinitrobutane (DMDNB) to help detect the explosive and identify its source.[1]

C4 is manufactured by combining the noted ingredients with binder dissolved in a solvent. The solvent is then evaporated and the mixture dried and filtered. The final material is an off-white solid with a texture similar to modelling clay.