... . Specifications: EI24, EI-28, EI-30, EI-35, EI-41, EI-41-2H, EI-48, EI-48-2H, EI-54,EI-57, EI-57-2H / 4H, EI-60, EI-66, EI-66-4H ... , EI68-4H, EI-76 ... .4. Applicable to all kinds of iron cores for power transformers and ballasts. EI lamination (silicon steel product)