Rennen Ultralite Hydrogen Bottom Bracket Street Park Dir MATERIAL: CNC machined from 7075-T6

MATERIAL: CNC machined from 7075-T6 aluminum in the USA

but can also be used with a traditional Pivotal seat

Always pay attention to your sprocket and make sure the teeth aren’t worn or clingy otherwise it might be noisy and time for a new one

Stretch-rib panels for flexibility and function

three axle blocks

Rennen Ultralite Hydrogen Bottom Bracket Street Park Dir MATERIAL: CNC machined from 7075-T6Rennen takes their commitment to BMX racing technology seriously and with the Rennen Ultralite Hydrogen Bottom Bracket at J&R Bicycles this is obvious. Engineered to be the lightest and smallest BB on the market, Rennen went even further and made this BB adjustable. Easily installed with special tools (included), once it is set up you'll be able to easily make precise adjustments to the chainline. Loaded with features, this BB uses Silicon Nitride