The Rio 500 is a portable, digital audio player that stores hours of exceptional, skip-free sound. You can listen to two hours of digital-quality music and more than 32 hours of spoken audio programs. Instantly create, customize and mix your favorite music and audio selections on your PC or Mac for playback on the Rio 500. Free audio management software makes it easy to convert tracks from your CDs or download audio content from the Internet. Expandable onboard memory, support for both Windows and Mac, and powerful software turn this player into an anytime, anywhere digital sound machine. USB Port for blazingly fast downloads 64MB onboard memory, expandable to 96MB Supports Microsoft Windows & Mac (iMac and G3) Audio software for encoding, managing, and playing digital audio files Manage onboard playlists AudibleManager software for spoken audio content (Windows 9X only) Skip free design - no moving parts Automatic bookmarking features for listening to spoken audio Upgradeable firmware provides future compatibility Uses a single AA battery for more than 13 hours of continuous play Palm size for easy portability