The Fox Dropframe is a half-way house between a full face and half shell. It doesn’t have a chin bar but there’s increased coverage at the side of the jaw, over the ear and back of the neck. It’s a distinctive design but it’s also incredibly lightweight for a helmet with this level of protection, and that helps it on its way to being one of the best mountain bike helmets for sale today.

We encountered the Varizorb EPS construction on the test winning SpeedFrame 18 month ago. Basically, it sandwiches together two types of closed-cell foam – one dark, the other light. They’re joined internally with a sort of zig zag border which, when compressed, dissipates impact energy more effectively. To offset those brain-damaging rotational forces, the helmet also features a low profile MIPS liner.

The Fox Dropframe has oodles of extra protection, but the genius is it still feels like a regular open face helmet

Surprisingly, there’s no retention device in this helmet but to be honest we never missed it because it’s so stable – it literally doesn’t move even on the roughest descents. It’s also incredibly comfortable and, unlike the Giro Switchblade, is dead easy to put on because you can pull those side extensions slightly apart, so you don’t catch your ears.

To secure the helmet there’s a short chin strap with a magnetic Fidlock SNAP closure, which is a lot less fiddly than the D-ring system on the Giro Switchblade.

With 15 vents, the DropFrame ventilation is really good for a bigger helmet. The neck can get a bit sweaty but this helmet is definitely our choice for winter rides. If we have one gripe it’s the lack of an adjustable visor. This one included is fixed high up, so you can’t see it but there’s not quite enough room to park a set of goggles cleanly.

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