Working principle: USB to four-port RS232 DB9 serial adapter, used to connect to serial devices via USB port, such as serial modem equipped with DB9, ISDN terminal adapter, digital camera, label writer, handheld computer, barcode scanner , PDA, etc. data transfer rate Connector: with standard USB A type male to standard 9-pin DB9 -232 serial male connector Conductor and shield: Tinned copper conductor and triple shielding the best data transmission rate. Powered by the USB port, no external power adapter is required. Simple installation, plug and play Compatible : for Windows (10/8.1/8/7XP), , Linux, etc. compatibility. Supports almost all serial COM ports Name: USB to RS232 adapter Cable length: 1.2m Interface: USB, RS232 Colour:black Material:PVC Size:6 x 6 x 3CM Package Contents: 1 * usb to Rs232 adapter Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.