Specialized's new top-line 2D lid is the main rival to Giro's Ionos pro road helmet. Super lightweight, our medium model hits the scales at a piffling 203g. A L/XL sized Limar Pro 104, is the only helmet we've had that beats the 2D on weight.
Light weight isn't everything, though, and thankfully the dual density foam body is reinforced with a Kevlar skeleton. The 2D uses high density around the sides to withstand impact, and lower density elsewhere to save weight.
On the head the helmet looks large but the fit found favour with just about all of our testers. Finer details like the lightweight 4X DryLite straps are softer than many and mounted on the underside of the helmet to keep them away from your face.
The adjustable retention system is basic to save on weight but it gets the job done. The 2D also comes with a removable peak.
Ventilation is up there with the best, but even with the mouthy front port we still found the Ionos cooler.