USE RX Alien Suspension Seatpost, 300x27.2mm At the forefront of technology and engineering excellence; extensive FEA development Diameter - 27.2mm, length - 300mm, adjustable travel - 30mm, material - CNCd 7075 T6 Aluminum Finish - hard anodized, layback/offset - 10mm (standard Alien), minimum Insert Depth - 100mm Alien Clamp - Cyclops clamp is forged and CNCd; Utilizes the latest aluminum manufacturing techniques