Deda superzero 317 stem the new superzero stem is the perfect combination of stiffness lightness and aero shape the flat top section of the stem results in a better aero performance and guarantees at the same time higher stiffness values designed for the most exigent riders material alloy 2014 screws crmo angle 82 handlebar 31 7 mm fork steerer 1 18 28 6mm