From the manufacturer:
The Cinelli crown jewel: our most advanced steel frame, made with the best materials and the highest technological quality. The Standard XCR tubing is a seamless tube in biphasic stainless steel, to create a light, unparalleled vibration absorbing, eternal bicycle frame. Pure state of the art. Available in 5 standard sizes as well as custom sizing.
Oversized 44mm head tube to join the 1.5" Columbus FEL monocoque fork. The new design of the rear stays dropouts improves the connection with the rear stays and reduces stress concentration. Completely hand built, in Italy.