This is SONY Walkman WM-30. An evolution model of WM-20 released in cassette case size. Prior to listing, each part will be cleaned, restored, drive system parts replaced, sound adjusted, etc. An overhauled and working item that is essential for continued use. High quality sound and very rare. There is almost no vibration or excessive noise that is common with cassettes, and the sound is powerful and good. Basic internal and external cleaning, machine part cleaning, reassembly, main belt replacement, Earphone mouth cleaning, head cleaning and mirror finishing, and roller cleaning. Cleaning volume parts. Motor restoration work. Azimuth adjustment, speed adjustment. Check each operation. Play, stop, fast forward, rewind, pause, auto shut off. Dolby NR, tape selector. Long-term operation test, hearing test by actual listening. Measuring instruments are used for speed adjustment, wow and flutter measurement, and azimuth adjustment. We use appropriate chemicals and oils during the repair process.