Product Description Product Features: 1. High-strength aviation-grade aluminum alloy tubing, 50mm adjustable preload suspension travel, and standard double-bolt clamps ensure riding safety. Coil spring damping provides a comfortable riding experience. Zoom is a professional bicycle component manufacturer from Taiwan, with reliable quality. It ranks first in global market share. 2. Coil spring suspension reduces bumps and impacts: Built-in coil springs and damping rubber absorb vibrations during riding, improving riding comfort and effectively alleviating impact and pain. Rebound force can be adjusted by tightening or loosening the bottom screw. 3. Adjustable rebound force and clamp angle: You can change the spring rebound force by adjusting the bottom screw to suit your weight and achieve the best riding experience. The saddle clamp angle is adjustable from -5 degrees to +18 degrees. Double-bolt clamps ensure safety and convenience. 4. How to select the size: 1. Check the diameter of your current seatpost; the size marking is on the bottom of the seatpost (you need to remove the seatpost from the tube to see the size marking). Select the same size from the options. 2. Measure the inner diameter of the frame tube. Suitable for most fixed-gear bikes, road bikes, mountain bikes, and general-purpose bikes. Suitable for riders weighing 50 kg/110 lbs to 180 kg/397 lbs. Note: Due to differences in monitors and lighting, the actual color may differ slightly from the picture. Please allow 1-3 cm deviation due to manual measurement. Material: Aluminum alloy; ZOOM; Model: SPS-405; Process: Frosted anodized; Color/Style: As shown in the picture. Includes: Option 1: 1 x Seatpost; Option 2: 1 x Seatpost, 1 x Adapter.