Philips CDM4 swing-arm CD mechanism
As the Philips single-beam swing arm type drive mechanism evolved, the extremely compact Philips CDM4 appeared. There are many versions of the Philips CDM4, the most representative of which are the Philips CDM4M with a hard resin top plate, and the die-cast Philips CDM4MD. With the appearance of the Philips CDM4, complete miniaturization of the drive unit, including the drawer mechanism indispensable in a front-loading system, became possible.