Essential 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 Essential kit utilizes a standard cap and bolt mounting system for a clean classic 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 Standard Headset Cap 1 x M6x35mm Cap Screw (Stainless Steel)