How to Use: Product Order Description (From bottom to top, the headset is installed on the upper and lower ends of frame head tube): Bottom File‑Lower Bearing‑Lower Headset‑Upper Headset‑Upper Bearing‑Urgent Loop‑Headset Cover‑Sunflower Top Cover Kit Specification: Item Type: Bicycle Headset Material: Aluminum Alloy Specification: 44-50.6mm (Use with 1.25 Small Cone Tube Front Fork) Applicable Situation: Frame Head Tube: Upper Tube Inner Diameter 44mm, Lower Tube Inner Diameter 50.6mm. Front Fork: Upper End Outer Diameter 28.6mm, Lower End Outer Diameter 33mm. Applicable Measurement Instructions: (The same four data can be applied) The inner diameter of the upper tube and the inner diameter of the lower tube, to obtain the inner diameter of the upper and lower tubes of frame; The outer diameter of the upper end and the outer diameter of the lower end are the outer diameters of the upper and lower ends of the front fork. Package List: 1 x Sunflower Top Cover Kit 1 x Headset Cover 1 x Urging Loop 1 x Upper Bearing 1 x Upper Headset 1 x Lower Headset 1 x Lower Bearing 1 x Bottom File