CAS 1220112-75-3 appears in our catalog under these names: O-(3-CARBOXYPROPYL)-O'-[2-(3-MERCAPTOPRO, o-(3-Carboxypropyl)-O′-(2-(3-mercaptopropionylamino)ethyl)-polyethylene glycol, HS-PEG-COOH (3 kDa), HS-PEG-COOH (10 kDa), HS-PEG-COOH (5 kDa). Offered by: Sigma-Aldrich, Biosynth, Iris Biotech. Available pack sizes: 100MG, 500mg, 1g.