cyclotetramethyene tetranitramine, a powerful explosive, was discovered as a by-product of RDX manufacture. In the nitric acid alone process it is formed in only small amounts. So ammonium nitrate and acetic anhydride are used with nitric acid in manufacturing a RDX/HMX mixture. It is most often used mixed with TNT which is called octol in shaped charges because of it high detonation rate and in applications where fragementation is desired because it produces more fragments at a higher velocity then does composition b. Like composition b it can be melt loaded.