DJC Suspension Seatpost Straight Pillar Headless Bike Seat Post Shock Absorber for City Bike FeaturesNo Clamp, Pay Attention to Diameter: No clamp with the seatpost, it will not works if you are MTB saddle. City bike saddle has clamp, it will works. Wrong diameter will not works as well. Make sure you checked what diameter you need before buy.Spring Suspension: A spring coil and damper rubber inside. Absorb the shocks and offer you good riding experience. Shock absorb travel 40mm/1.73in, seatpost total length 350mm/13.7in. Rebound Force Adjustable: The suspension seatpost fit for riders weight 50kg/ 110lbs to 100kg/ 220lbs. Bottom screw can adjust spring rebound force. Clockwise the bottom screw if you are heavy, anticlockwise it if you are lightweight.High Quality : Body aluminum 6061 alloy. Comply to international bicycle safety standard ISO 4210. Sand blast anodized surface treatment. Weight: 25.4mm-420g, 27.2mm-470g, 28.6mm-490g, 30.9mm-495g2 Years Warranty: Quality durable. We offer 2 years warranty and 1 month return without any reason. About This seatpost produced by HL CORP which was founded in 1991. The company create famous bike parts in the world with good quality, reasonable price, enjoying good reputation in the industry. HL CORP products are exported far to Europe, USA, ASIA. Its manufacturing and sales are in the leading position in the industry.