E cores ETD29, type TDK/Epcos B66358. To IEC 61185. With optimized weight/volume/power ratio. Made of silicon ferrite materials; refer to the corresponding data table at the end of the cores section. The corresponding core without air gap (dimension g = 0) must be ordered along with the gapped core (dimension g). Both cores will produce the specified AL reference value; Basic dimensions of a ready-to-use transformer or signal transformer: horizontal L 35.5, W 35.5, H 25.5 mm, vertical L 24, W 35.5, H 41.2 mm. Technical attributes (type, dimension g, AL value, material type): B66358GX197, 0 mm, 2250 nH, N97