These baseplates are the foundation that keeps Chris King headsets turning with legendary smoothness. Manufactured from high-quality stainless steel or titanium, Chris King makes replacement baseplates for all standard sizes and a number of ingenious solutions for those that need something a little special to make their headset work. - Engineered and manufactured in Portland, Oregon USA - Devolution baseplates are a stainless steel solution that allow Chris King headsets to adapt to a wide variety of steerer tube sizes - 30.0mm for 1.5 lower bearing and 1 1/8" steerer