Movimento centrale standard a cono quadrato BB UN300 per pedivelle JIS Pro Grado 68mm Scocca 110mm Perno BSA 68mm Cuscinetto a cartuccia con perno cavo senza bullone di fissaggio. Linea catena regolare. Ricambio resistente per bici da strada e MTB

UN300 JIS Square-Taper BB with 110mm Hollow Spindle
✔️ 68 mm shell, 110 mm hollow spindle, single unit for JIS cranks

The UN300 bottom bracket is a sealed cartridge unit designed for JIS square-taper cranksets. It’s a common replacement for road and mountain bikes, delivering stable chainline and durable operation in a 68 mm shell.

✅ Fits JIS square-taper cranksets
✅ Hollow spindle
✅ BB Shell Width: 68 mm
✅ Spindle Length: 110 mm
✅ Cartridge bearing, UN300-style

💡 What is a bottom bracket cartridge used for in JIS square-taper crank setups?

A handy answer: It provides a sealed, cartridge-style bearing setup that fits JIS cranks, helping maintain chainline and smooth rotation.

- Sealed cartridge bearing for smooth rotation
- 68 mm shell width with 110 mm spindle
- Fits JIS square-taper cranksets on road and MTB
- Easy replacement on compatible bikes