bicycle steer tube - WAKE bicycle steer tube extender MTB bicycle handlebar riser Head Up Adapter Aluminum Alloy This bicycle steer tube extender is made of high strength CNC machined 6061 T6 aluminum alloy. It is suitable for mountain biking to raise the handlebars steer tube,Made of high strength CNC machined 6061 T6 aluminum alloy. Suitable for mountain bike to raise the handlebars steer tube. Can the steer tube extend of 35mm maximum. Easy installation, just connect up the original steer tube.