NEVER OPENED...NEW IN BOX.. Use on windows 3.1, Windows 95 and Windows 98...Many features...see photos. The IBM 56K Vintage Modem Internet Kit, manufactured by CPU Builders in the United States, is a PCI modem card with V.90 standards. This modem, model 10L7389, offers a reliable and high-speed internet connection for vintage computers. With its compatibility with PCI ports, users can easily upgrade their older systems to gain access to the internet at faster speeds. Perfect for those looking to connect to the internet with a retro feel, this modem kit is a unique and nostalgic addition to any computer setup.