Windows Media Components for QuickTime

Windows Media Components for QuickTime, also known as Flip4Mac WMV Player by Telestream, Inc. was one of the few commercial products that allow playback of Microsoft's proprietary audio and video codecs inside QuickTime for macOS. It allowed playback of: Windows Media Video 7, 8, 9, SD and HD Windows Media Audio 7, 8, 9, Professional and Lossless It also included a web browser plug-in to allow playback of embedded Windows Media files in web pages.

Source: Wikipedia — Windows Media Components for QuickTime (CC BY-SA 4.0)