We provide 2 arm-, 3 arm- and 4 arm branched type- Activated PEGs. NOF supply various Activated PEGs possessing like maleimide, aldehyde, amine and activated NHS as the terminal functional groups. Although aqueous solutions of higher-molecular PEG derivatives tend to show increased viscosity, use of higher-branched Activated PEGs, such as 4-branched derivatives, is useful to reduce the viscosity of the relevant aqueous solutions, even without any change of the molecular weights. Collaborating with Enzon Pharmaceuticals, Inc., NOF has a right to sell their unique Lysine Branched PEG (SUNBRIGHT LY series) for customer research purpose only. Lysine Branched PEG has been already used in several marketed PEG-drugs such as PEGUSIS®, MACUGEN® and CIMZIA® for 10 years.