Pro StackRight Headset Spacers and Top Cap Kit Headset spacers that look great and stay that way. No more misaligned headset spacers. Wheels MFG has developed StackRight technology which locks spacers together for a clean, sleek look. The Pro kit features a flat top cap design which conceals the stem bolt for a custom finished look. Details: Headset spacers for 1-1/8" fork steerer. Inner Diameter: 28.9mm Outer Diameter: 34.4mm Precision-machined 6061 aluminum Kit Includes: 2 x 10mm Spacers 2 x 2.5 Spacers 2 x 1.5 Spacers 1 x 5mm Spacer 1 x Headset base Cap 1 x Flat Top Headset Cap 1 x M6x35mm - Cap Screw (Stainless Steel)