Backed by a 110-year warranty and constructed in Fletcher, NC, the 110-Series headset is designed with no compromises in quality, performance, or strength. Integrated bearings fit directly into compatible head tubes without the need of a bearing press. Features: 7075 T-6 aluminum cups machined in Fletcher, NC Aluminum dual seal crown race protects lower bearing 110 year warrranty Sealed stainless steel bearings Specifications: Compatibility: Tapered 1-1/8" to 1-1/2" steerer tubes, or straight 1-1/8" steerers with a conversion crown race (sold separately) Bottom Head-Tube Diameter: 52.1mm Crown Race Diameter: 39.79mm Bottom Stack Height: 1mm Weight: 34g