Features: 1. High-strength aerospace aluminum alloy tube with 50mm adjustable preload suspension travel. Standard 2-bolt clamp design ensures secure saddle attachment and riding safety. Coil spring damping system provides a comfortable riding experience. Zoom is a professional bicycle component manufacturer from Taiwan, known for high-quality products and leading market share globally. 2. Spring coil suspension system reduces bump impact. Built-in coil spring and damper rubber absorb vibrations during riding, enhancing comfort and reducing shock and discomfort. Rebound force is adjustable by tightening or loosening the bottom screw. 3. Rebound force and clamp angle are adjustable. Adjust the bottom screw to customize spring rebound force according to rider weight for optimal comfort. Saddle clamp angle can be adjusted from -5 to +18 degrees. Dual-bolt clamp design ensures secure attachment and easy installation. 4. How to Choose the Size: - Check your current seatpost diameter. The size is usually marked on the lower part of the post (requires removal from frame to view). Select the same size from available options. - Measure the internal diameter of the bike frame's seat tube. Compatible with most Fixed Gear bikes, Road Bikes, Mountain Bikes, and Universal Bikes. Supports rider weight from 50kg (110lbs) to 180kg (397lbs). Note: Actual color may vary slightly due to monitor differences and lighting conditions. Allow 1-3cm variation due to manual measurement. Material: Aluminum Alloy Brand: ZOOM Model Number: SPS-405 Process: Frosted Anodization Color/Style: As shown in picture Package Options: Choice 1: 1 x Seat Post Choice 2: 1 x Seat Post, 1 x Adapter