Upgrade your drivetrain with the Box One Oversized 20mm Cassette Spacer Kit , designed for precise chainline adjustments and optimal performance. This kit includes adjustable spacers ranging from 2mm to 6mm , allowing you to fine- tune your cassette spacing to perfection. Made from 6061- T6 aluminum and CNC- machined for strength and precision, these spacers are extremely lightweight , with a total weight of only 3g . The anodized finish ensures long- lasting durability while maintaining a sleek, professional look. The kit includes three 2mm spacers , giving you the flexibility to adjust your cassette setup to your exact needs. Compatible with OS spline drivers , the Box One Oversized 20mm Cassette Spacer Kit is the ideal solution for BMX racers looking to optimize their drivetrain performance with minimal weight. View Whitepaper: Box® - Stealth Hubs Whitepaper 06.12.25