Vktech USB To RS485 TTL Interface Board Double Function Double Protection Module USB2.0 standard, backward compatible, in line with the standard RS485 Support Windows98/ME/2000/XP/WIN7/Vista, Linux, Mac Self-powered from USB Size:Approx. 7.8cm x 1.9cm X 2cm - 3.07inch x 0.75inch x 0.79inch