The Chris King 1.5R Devolution NoThreadSet is a reducer headset, meaning it allows a bike with a 1.5" headtube to accept a 1-1/8" fork. It comes with a reducer sleeve, and a specially machined crown race designed to bear the reducing responsibility. The outer diameter of the crown race is 1.5" wide providing the surface on which the bearings sit, the central diameter is just 1-1/8" to fit the steerer, and it is specially tapered to fit the reducers.

Apart from that, the Chris King 1.5R Devolution NoThreadSet has the same PreLoader, and the same surgical grade stainless steel sealed bearings as the 1.5 NoThreadSet. And, you get the same 10 year King warranty. If you decide down the road that you want to run a 1.5 fork -- no worries -- just get a new crown race & top cap, and ditch the reducers. Nine anodized colors: Black, Pewter, Silver, Navy, Red, Green, Gold, Pink, and Mango. Cup skirt length: 19mm; Upper stack height: 21.2mm; Lower stack height: 14.75mm. 250g not including the PreLoader (72g.)