SUPOW(TM) Mountain Bike Headset Clock/MTB Bike Bicycle Watch/Handlebars Clock/Headset Handlebar Riser Clock/CNC Alloy Stem Top Cap Headset With Clock Waterproof, Shockproof Material: Aluminium alloy Top Diameter: 35 mm. Bottom Diameter: 15mm Weight: 25g. Height: 11mm This item doesn't come with Bolt.