Using FT232RNL chip solution, high-speed communication is stable, reliable and has good compatibility Onboard (transient voltage suppressor), which can effectively suppress surge voltages and transient voltages in the circuit, and protect against- and static electricity On-board self-restoring fuses and protection diodes stable current and voltage output, prevent overcurrent and overvoltage, and improve impact resistance. Onboard RS232/485 communication switching circuit, users can switch the communication type by toggle switch Built-in RS485 output terminal 120R resistor, which can be enabled by toggle switch for flexible switching There is an external LED indicator light for easy viewing of power supply and signal transceiver status. Using ABS environmentally friendly shell, small size, portable and easy to use, high cost performance Due to different batches, the appearance, color and printed words of the product , which not affect the use. Colour:Black Material:Plastic Package Contents: 3 x USB to RS232/485 converter 3 x USB 3 x screwdriver Only the above package content, other products are not included. Note: Light reflection 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.