... Oe, 2750 Oe, or 4000 Oe, etc. Base film material: Polyester Color: Black, Brown Magnetic Stripe General Characteristics Coercivity Hc: 300 Oe, 650 Oe, 2750 Oe ... , or 4000 Oe, etc.Base film material: PolyesterMagnetic layer material: FerriteColor ...