The magnetic cores (also called toroids) must be inserted before making the joints. The toroid position along the cable section of the joint hole is irrelevant. After making the joints, the toroids can no longer be extracted and the shielding cables are installed. In general four shielding cables are positioned for every source cable. The length of the shielding cables must be equal to the joint hole. The shielding cables must be positioned symmetrically, the minor, unavoidable asymmetries due to installation do not affect shielding efficiency at all.

At the end of installation of the headers shielding is completed and appears as a strong and secure "armour" that assures reduction of magnetic fields like no other shielding is able to offer.