Rennen Ultralite Hydrogen Bottom Bracket gear-size-39-9t Constructed from CNC machined aluminum

Constructed from CNC machined aluminum

*2-way stretch polyester spandex

Adjustable rear strut for a customized fit

1-1/8" Step Down to 1": 2

75" BB HEIGHT: 12" REAR CENTER: 15

Rennen Ultralite Hydrogen Bottom Bracket gear-size-39-9t Constructed from CNC machined aluminumRennen 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