These are amorphous cores which include amorphous saturable core (FBC), common-mode choke coil (FTF) etc. These amorphous cores are in different sizes and they made of different materials. The cores can be used to smoothen switching power supply outputs.

• Small and lightweight when compared with ferrite cores and dust cores
• Help stabilize inductance
• Excellent DC bias characteristics
• Amorphous toroidal without gap core
• Low core loss at a high frequency