ITEM NAME:Mountain Bike Seat Post Aluminum Alloy Seat tube 25.4/ 400mm Lengthened Product Description Description: Features: Light weight, high hardness, corrosion resistance, long service life. Size: 25.4/ 400mm Color:Black Material: Iron Weight: 325g Included: 1 X Â Seat tube.Size: 25.4/ 400mm. Included: 1 X Seat tube. Material: Iron. Light weight, high hardness, corrosion resistance, long service life. If item is defective after 3 months, you can still send it back to us.