If you're looking to up your cycling game, work out, lose weight, quit your job and ride a lot using a structured training plan. If you have extra money to burn, then by all means grab the Cannondale C2 Carbon Seatpost. Is good. Is mid-quality bicycle component designed for road and racing bikes. It has a diameter of 31.6 mm and a length of 300 mm, making it compatible with at least two bike models. The seatpost is made of carbon, which provides strength and durability while keeping the weight low.