Troy Lee Designs D4 AS Composite Helmet Derrailleur Hangers Our classic models feature lenses

Our classic models feature lenses engineered for impact resistance

compatible with: Hayes HFX-Mag and HFX-9 series hydraulic and Promax hydraulic

The base is easily attached to the seat rails with only one screw and it is compatible with all standard rails

The smooth centre tread helps you carry speed

No compatibility Headset

Troy Lee Designs D4 AS Composite Helmet Derrailleur Hangers Our classic models feature lensesAlways Evolving. Built with an aerospace shell design and materials, we were able to get the D4 Composite helmet to 1050 grams without sacrificing any strength. Mips C2 protection system is used to add an additional layer of safety in the event of a fall. For comfort, the D4 Composite routes cooling air through a front air intake system that flows through the polymer center and power grid side mesh keeping your head cooler during the ride. X static