RS Pro Common Mode Chokes 2 x 0.7mH - 2 X 3.3mH. RS Pro Toroidal chokes are high quality and are an efficient means of filtering supply lines. The common mode chokes have in- phase signals of equal amplitude allowing equipment to meet stringent electrical radiation specifications. Wide frequency ranges can be filtered by using a high and low inductance Toroidal chokes in a series. Different mode signals can be attuned substantially when used together with input and output capacitors. Applications. Data storage systems Digital video camera Industrial systems Professional audio