StackRight Headset Spacers Pack Headset spacers that look great and stay that way! No more misaligned headset spacers. Wheels MFG has developed StackRight technology which locks spacers together with an interlocking channel for a clean, sleek look. Details: Headset spacers for 1-1/8" fork steerer. Inner Diameter: 28.9mm Outer Diameter: 34.4mm Precision-machined 6061 aluminum Pack Includes: 2 x 10mm Spacers 2 x 2.5 Spacers 2 x 1.5 Spacers 1 x 5mm Spacer