ESU 51960 - Permanent magnet (LFCM)
Permanent magnet as No. 220560, for Armature 217450, D=24.5mm, for engine plates 216730, 211990, 228500
Charlie's Tip: For LFCM motors. If your old Marklin locomotive has armature 217450 (look at its parts list, it may say in German "Anker 21745"), this is what you need to convert the motor to 3-pole DC.
You will need this to convert a Marklin 3048, the 5-pole cover will not fit the motor.