With this item, it is easy to add an RS-485 interface to a PC via RS-232.No power required, uses TD as power source. This does not need any AC or DC power.Interface: Compatible with for EIA/TIA RS-232C standard and RS-485 standard.Working mode: Asynchronous, half-duplex, differential transmission.T-ransmission media: Twisted-pair or shielded twisted pair (STP).It uses a particular pump to gain power from RS-232 signal (RTS, DTR, TXD) without initializing the RS-232 series interface.RS232 to RS485 Converter only, other accessories demo in the picture is not included Specifications: Item Type: RS232 to RS485 ConverterMaterial: PCSize: 93x32mm/3.6x1.2inColor: As shownData Transfer Rate: 300-115200bpsOperating Distance: 1200m for RS485, 5m for RS232Environment: -10-85/14-185, 5-95% RHQuantity: 1 Pc Note: No retail package.Transition: 1cm=10mm=0.39inchPlease allow 1-3mm error due to manual measurement. pls make sure you do not mind before you bid.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you Package Includes: 1 x RS232 to RS485 Converter