2 pcs CH340 USB to RS232 Male Adapter Serial Port DB9 9 Pin Male Converter Adapter CH340 Chip with RS-232 DB9 Female to Female Adapter for XP/Vista/Win7/8/10. CH340 chip : CH340 is a USB-to-serial conversion chip, which is very suitable for the interface between the PC and the PC through USB at close range, instead of the RS232 conversion, which makes the connection between the PC and the peripherals faster and simpler.
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