1. Standard size, enhanced hardness, giving you a wonderful ride. 2. Made from high quality aluminum alloy material, which is very durable. 3. Made your bike more excellent. PS:CNC precision aluminum alloy cover is used above the head tube, no need to install the hanging core, 38cm full length is equivalent to the center length of Fengxing head tube 35cm, Carbon fiber front fork uses 18-specification screw pitch 1.0/1.25/1.5 (for litepro/Wacako uses 1.25 teeth, for SILVEROCK uses 1.0 teeth) Double tube clamp locking advantage: solves the existing market can not lock the defect Length: full length 38cm Suitable for 14-20 inch car models installation Specification:M18 Colour:Silver Material:aluminium alloy Package Contents: 1 * Bicycle Stright Steerer Tube kit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.