Rennen Ultralite Hydrogen Bottom Bracket Street Park Dir Post weld 4Q Baked heat-treatment

Post weld 4Q Baked heat-treatment

three axle blocks

but can also be used with a traditional Pivotal seat

and is neither too tight

19mm spindle

Rennen Ultralite Hydrogen Bottom Bracket Street Park Dir Post weld 4Q Baked heat-treatmentRennen 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