The FT4222H Interface B is a USB-to-UART/FIFO interface chip from FTDI (Future Technology Devices International). It's designed to provide USB connectivity to devices requiring UART (Universal Asynchronous Receiver-Transmitter) or FIFO (First In, First Out) communication. The FT4222H chip is typically used in embedded systems, industrial applications, and communication devices to establish USB connections for data transfer.

The FT4222H Interface B Windows driver is a software package that allows Windows operating systems to properly communicate with and control devices using the FT4222H chip.