MAGNETIC PRESSURE DISK CDM12

Sometimes called (by JR) a CD Puck, this holds down the CD on the CD Players CDM3, CDM4, CDM12, & CD-Pro and is supported by the Clamp Arm.

Third photo shows the difference between a new and worn out - from misalignment - puck.

Replacement and alignment instructions are here (PDF)

Wurlitzer technical info and parts catalogs are available from this clickable link