Many cars use something called titanium wheel lug bolts. A titanium wheel lug bolt, bolts the wheel and brake rotor directly onto the hub. This makes changing the brake rotor easy, but adding hassle of lining up the wheel and brake rotor when mounting wheels.
The seats of a titanium wheel lug bolt just like a titanium lug nut and can be found with a hex head or tuner style with a conical seat or spherical seat or flat seat.
Now there are three kinds of wheel hub base seat: conical seat, spherical seat and flat seat. We should choose right wheel lug bolt according to different wheel hub base seat. If we choose wrong one, the joint part will not fit and then damage the appearance of wheel hub, affecting the strength of hub and traffic safety.
The choice of titanium lug bolt is also different from country to country. Different country could use different bolt for the same car. In China, Volkswagen and Benz more use spherical bolts. In other country, Volkswagen more use cone bolts.
So when clients buy bolts, you should know the seat type of the bolts and the using habit in this country.