Carver Bikes bottom bracket. Set up tubeless (front tire is currently tubed but includes a tubeless style presta valve for going back to tubeless). Brakes don't stay firm so either a proper bleed ( I don't have a bleed kit) or a new bleed/fill plug may be necessary. Needs new Shimano/Magura brake oil. Chain guard has been cut off to save weight. Crank Brothers Candy SL clipless pedals included. Overall a lightweight, fun bike in decent condition albeit with the aforementioned quirks. If you've got a medium sized root beer Rig I'd be willing to trade.