Abstract: A personal electromagnetic security unit for shielding portable electronic communication and data devices such as cell phones and computers. The shielding unit includes a coated liner construction in which a high-attenuation metallized fabric is coated with a second attenuating material to enhance the electromagnetic absorption or reflection characteristics of the unit. This two-part conductive layer forms the inner liner of the shielding unit, with the coated side being protected by the unit's exterior material and preferably an intervening layer of padding.