About Wheels Aluminum Headset Spacer: Machined aluminum spacers for tuning ride height- 1 kit includes storage box, 10 different keyed and non-keyed spacer sizes: (20) 1.5mm silver, (20) 2mm silver keyed, (20) 2.5mm silver, (15) 2.5mm black, (15) 5mm silver, (10) 5mm black, (5) 7.5mm silver, (3) 10mm silver, (3) 15mm silver, (3) 20mm silver- 1-1/8 kit includes storage box, with selection of non-keyed spacers: (15) 1.5mm silver, (15) 1.5mm black, (15) 2.5mm silver, (15) 2.5mm black, (15) 5mm silver, (15) 5mm black, (5) 7.5mm silver, (5) 7.5mm black, (5) 10mm silver- Packs include: (1) 2.5mm, (1) 5mm, (1) 7.5mm, (1) 10mm.