The Extralite UltraHubs are one of the lightest hubs currently available. These truly are a work of art. They are crafted from 7075TX aluminium, with 2RS external bearings and 20-32 internal bearings. The axle is a multi-shaped 20 - 17mm design which adds to the hubs amazing stiffness. Oversized disc mount prevents twisting from braking forces. Extra sealing is added for the hubs to help keep the gunk out, hard anodized and laser etching gives excellent long term durability. The hubs are silky smooth and Extralite's implementation of the micro-tuner ensures that bearing preload is exactly spot on. The rear has a 30T titanium pawled freewheel which gives amazing acceleration and response to the drivetrain. Both hubs require straight pull spokes, the front non-disc side is laced radially.