Box One Quantum Cassette Race Hubset Size:20mm but will also work with

but will also work with other popular gyros on the market

Strong butted tubing

Smaller 16" Wheels - The Perfect fit for for 5-8 years olds (3ft - 3ft 6 / 90cm - 105cm)

A proprietary blend of compounds provides for the fastest and grippiest tire out there

Box One Quantum Cassette Race Hubset Size:20mm but will also work withFor more than seven years, Box Founder Toby Henderson has been trying to build a reliable 20 mil rear cassette hub without creating a new cassette standard, the problem was fitting durable bearings between the cassette body and the oversize axle. The rear Quantum hub overcomes this by using the type of one piece driver commonly found on freestyle hubs. Each hubset includes a 1 piece, 16 tooth driver supported by 3 large, roller bearings. Inside the