- Road racing/training rim based on the Aerohead rim with a wider footprint that allows for a more aerodynamic rim/tire combination when paired with a 23c tire - Tire profile mimics the characteristics of a tubular - Hollow core aluminum with machined sidewalls for improved braking - O/C version: Off center design allows for dramatically improved spoke tension on a dished wheel, the A23 OC allows for a more aerodynamic rim/tire combination when paired with a 23c tire - US made A23 rims now feature a tubeless ready design. Combine that with the new 21mm wide Velotape kit and you have a fool-proof Road and Cyclocross tubeless tire setup