This listing includes 35 used/tested toroidal inductors labeled 603123 4121, designed for EMI/RFI filtering or use in switching power supplies. These components feature copper wire windings over a ferrite toroidal core and are built for through-hole PCB mounting.

Though not new, each piece was removed from working systems and visually inspected.

✅ Used – Tested for functionality
✅ Toroidal coil for EMI suppression or energy storage
✅ Through-hole mount
✅ High-current design with ferrite core
✅ Ideal for power electronics, industrial repair or prototyping