bicycle Aluminum Wheelset Improved 58mm rim profile - fast and stable the signature Zipp wheel ABLC Saw tooth dimple design helps manage air flow around the rim, and contributes to create a faster, more stable wheel Industry leading Showstopper brake track: powerful and consistent braking, even on the wet 77/177 hub set, reliable & durable, proven in the Spring Classics. No pre-load adjustment required Aero performance, durable and light weight