Universal Driveshaft Loop is designed to prevent the driveshaft from entering the driver`s compartment in the event of a driveshaft, yoke or U-joint failure. NHRA/IHRA mandated in any drag car quicker than 14. 00 seconds, or any car equipped with slicks. Also mandatory in most circles track classes. Loop is constructed of " thick x 2" wide mild steel and is fully adjustable to fit most cars.