Description Features: 1. High-strength aerospace aluminum alloy tube, 50mm adjustable preload suspension travel, standard clamp with 2-bolts ensures safety during riding. Coil spring damping provides a comfortable experience. Zoom is a professional bike component manufacturer from Taiwan, known for high quality and leading market share. 2. Spring coil suspension reduces bump impact: Built-in spring coil and damper rubber absorb vibrations while riding, enhancing seat post comfort and improving shock absorption. Rebound force is adjustable by tightening or loosening the bottom screw. 3. Rebound force and clamp angle adjustable: Adjust the bottom screw to customize spring rebound force according to your weight for optimal riding comfort. Saddle clamp angle can be adjusted from -5 degrees to +18 degrees. Dual bolts secure the clamp for added safety and easy installation. 4. How to choose the size: Check your current seatpost diameter; size is marked on the lower part of the post (must be removed from frame to see). Select the same size from available options. Alternatively, measure the inside diameter of the frame tube. Suitable for most fixed gear bikes, road bikes, mountain bikes, and universal bikes. Supports rider weights from 50kg (110lbs) to 180kg (397lbs). Notice: Actual color may vary slightly due to different monitor displays and lighting conditions. Please allow 1-3cm variation due to manual measurement. Material: Aluminum Alloy Brand: ZOOM Model number: SPS-405 Process: Frosted anodized Color/Style: As shown in picture Includes: Option 1: 1 x Seat post Option 2: 1 x Seat post, 1 x Adapter