BontragRr xxx HCM carbon MTB Cycle Road Bike Seat Post 27.2/30.9/31.6*400mm Bontragr HCM full carbon fiber bike seat post Length 400mm, 0mm setback, UD gloss finish Availabel size: 27.2/30.9/31.6*400mm Unith weight: 170g with metal clamp on 27.2x400mm Warranty:1 Years under normal using condition