Features: 1. High-strength aerospace aluminum alloy tube with 50mm adjustable preload suspension travel. Standard 2-bolt clamp design ensures secure attachment and riding safety. Coil spring damping system provides a smooth and comfortable ride. Zoom is a professional bicycle component manufacturer from Taiwan, known for high-quality products and leading global market share. 2. Spring coil suspension reduces bump impact. Integrated coil spring and damper rubber effectively absorb vibrations during riding, enhancing comfort and reducing shock and fatigue. Rebound force is adjustable by tightening or loosening the bottom screw. 3. Adjustable rebound force and clamp angle. The bottom screw allows adjustment of spring tension to suit rider weight for optimal performance. Saddle clamp angle is adjustable from -5 to +18 degrees. Dual-bolt clamp design improves stability, safety, and ease of installation. 4. How to choose the size: a. Check your current seatpost diameter. The size is usually marked on the lower section of the post (remove from frame to view marking). Select the same size from available options. b. Measure the internal diameter of the bicycle frame’s seat tube. Compatible with most fixed gear bikes, road bikes, mountain bikes, and universal bike frames. 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 Includes: Option 1: 1 x Seat Post Option 2: 1 x Seat Post, 1 x Adapter