The Sony WM-F66 is a compact cassette player featuring AM/FM radio functionality. It is designed for portable audio playback, making it suitable for on-the-go listening. The device typically features a sleek and simple design, often with a retractable antenna for enhanced radio reception. Key specifications include a built-in speaker, headphone output, and a variety of playback features such as auto-stop and tape counter. The WM-F66 is powered by batteries, allowing for extended usage without the need for a power outlet. It also includes a belt clip and a carrying strap, making it user-friendly for those who enjoy outdoor activities or traveling. The inclusion of radio tuning controls adds versatility, enabling users to easily switch between cassette playback and FM/AM radio listening.