Dual Cardan joints allow for smoother power transfer in the front drive train of your Touring Car when the wheels are turning. Installing these in your car will allow for the car to drive smoother and have increased steering especially in tight corners. The RSD DCJs from Reflex Racing work with both the TC6 and the TC6.1 so long as you are using a 5x10x3 bearing in the TC6 and a 5x10x4 bearing in the TC6.1. You must also use a Hex Hub adapter with a larger axle hub opening like the ones for the HB TCX, Yokomo BD-5 or 3Racing Sakura line of vehicles. Each package includes 2 DCJ’s.