Dimension Two-Bolt Seatposts provide a sturdy and durable saddle perch for cross country and all-mountain riding in three diameters, rigorously tested to ISO 4210 Mountain standards. FEATURES: Constructed with AL-6061-T6 aluminum Shot-peened finish SPECS: Offset: 0mm Color: Matte Black Clamp Style: Standard Rails Material: Aluminum Length: 350mm Diameter: 30.9mm Defined Color: Black