The zipp 303 firecrest carbon clincher wheel delivers everything you could ask for including a heritage forged in the spring classics at the center of the 303 firecrest carbon clincher is the 77177 hubset an innovation that results in improved stiffness durability simplicity and versatilitythe zipp 303 features a wider rim which provided extra durability and improved aerodynamics that wider rim also led to the development of the revolutionary firecrest platform and now the revolution co