Depending on the wheels and vehicle hub, lug bolts vary in the thread, length, seat type, or others. Thread engagement refers to how much contact your Audi RS5 lug bolt has, or how many complete turns before it is tight. For your safety, proper thread engagement must be met. Common seat types of wheel bolts include conical seat, ball seat, flat seat, etc. If you get aftermarket wheels, it is important to confirm the lug seat type of your wheels. You can get information from the wheel manufacturers. Making sure you have lug bolts with the correct seat type that will fit safely.