Backed by a 110-year warranty and constructed in Fletcher NC the 110-Series headset is designed with no compromises in quality durability or finish quality. Zero stack uppers press into head tube with very little stack height. Lowers are either zero stack or external cup.Sealed stainless steel bearingsCarbon-friendy compression ring captured in top cover keeping shims in place7075 T-6 aluminum cups machined in Fletcher NCAluminum dual seal crown race protects lower bearingInterlok spacer compatible110 year warrranty