Uh, Burn, Esbits are hexamine with a binding agent to make them a little less crumbly than the ancient USGI hexi tabs were. In a tannish package with UK MoD markings on it, they are simply listed as such, rather than the Esbit brand name. The binding agent might make them a little less toxic, but hexamine is hexamine is one VERY irritated urinary tract and heart burn so bad you are curled up wanting to die.