Shimano - CS-R8101 Ultegra 12 Speed Cassette import_2021_12_08_175012 Suitable for ages 4-6 or

Suitable for ages 4-6 or alternatively

4” tires mounted on wide aluminum double wall 36H rims with 3/8” female axle front hub and 9T cog sealed bearing cassette rear hub

Designed to repel dirt

Reduces friction and frees seized parts

Shimano - CS-R8101 Ultegra 12 Speed Cassette import_2021_12_08_175012 Suitable for ages 4-6 orSHIMANO ULTEGRA 12 speed HYPERGLIDE+ Road Cassette Sprocket The uninterrupted shifting experience of the ULTEGRA R8101 12 speed cassette range lets you climb, sprint, or cruise without stopping to think about your next gear change. Larger driving cogs maximize drivetrain efficiency and create compatibility with both Shimano 11 and 12 speed FREEHUB bodies.