The wire should be securely attached to the sub-frame or chassis leaving the 60mm diameter tow-eye protruding from the bumper or grille. A soft tag is attached in case the loop drops back inside the bumper or grille. This allows the tow-wire to be retrieved easily.
The wire has been tested and has a breaking point in excess of 2.6 tons, which is approximately twice the weight of even a large motor sport vehicle.
The MSA Regulations recommend four per car (like the BTCC).