This adapter converts telephone & fax modem cables fitted with a UK telephone plug to the international RJ11 standard.It is designed for 3 types of useage:for connecting a UK telephone to a modemwith other international telephone adapterson its own for countries which utilize the RJ11 standard (for a list of these countries please see product code PH.USA at the end of the international adapters section)This reverse wired adapter is 8cm long and made using 4 core cable to maximise compatibility.