The C3 M coating, water soluble Polyester base equivalent to C3 of AISI, improves punchability up to three times as compared to uncoated electrical steel. It is resistant to normal operating temperatures & is highly corrosion resistant (C3 M coatings can be used as a corrosion undercoat for C6 coatings) but will not withstand stress-relieving annealing (SRA). It is suitable for applications where high level of inter laminar resistance is required like small and medium sized motors as well as small transformers.