Star Tech.com Industrial RS232 to RS422/485 Serial Port Converter with 15KV ESD Protection Convert an RS232 data signal to either RS485 or RS422 with this wall-mountable, ESD-protected adapter Features RS232 to 2/4-wire RS485 or RS422 conversion Supports RS422 & RS485 auto detect & manual switching ±15KV ESD protection on all signal pins