It is a 1 port 75 Ohm BNC E1 to 120 Ohm RJ45 balun impedance convertor, plastic casing. 75Ohm ... is a 1 port 75 Ohm to 120 Ohm impedance convertor, plastic casing.Description:75/120 Ohm impedance matching baluns allow users ... G.703 standard. The balun can perform 120 ohm to 75 ohm signal conversion as well, giving the device ... 2.03 cm) DTypical Application: Balun Impedance Converter, 75 Ohm BNC E1 to 120 ...