Giro Aether Spherical helmet long term review

Giro's Aether combines a novel approach to rotational force dissipation with excellent ventilation, cool looks, and a best-in-class fit system.

Photo: Dan Cavallari |

Review Rating


Roc Loc Air fit system; MIPS Spherical system to address rotational forces


Excellent fit system; unique MIPS application; comfortable, attractive, and well-ventilated


Expensive; not the lightest option for a high-end helmet

Our Thoughts

The Aether MIPS is the best helmet on the market for road and gravel riders.

Size Reviewed



333 grams





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I’ve been riding the Aether Spherical helmet from Giro for the better part of two years now, and I have yet to find a better helmet on the market. The Aether combines excellent ventilation with an equally excellent fit, all packed into a truly unique MIPS design intended to help disperse rotational forces in the event of the crash. It has remained my favorite helmet for two years, and so far nothing has come close to unseating it.


Aether’s unique construction

MIPS Spherical
Two EPS shells, one within the other, rotate independently in the event of a crash. Photo: Dan Cavallari |

The Aether features a shell-within-a-shell construction, sort of like a ball and socket design. It wasn’t the first helmet to get this treatment — Bell’s Zephyr helmet was the first, and since Bell and Giro used to be closely aligned companies, it wasn’t surprising to see the design come to Giro helmets too.

MIPS developed the design with Giro to accomplish what all MIPS systems do: to dissipate rotational forces in the first milliseconds of an impact. The inner EPS shell rotates within the outer EPS shell in this case — with a low-friction layer in between to ensure the EPS shells don’t bind on each other — meaning those rotational forces go to the helmet’s independent rotation rather than to your head. (Giro recently introduced this design to the mountain bike world with its Manifest helmet.)

Since there’s no traditional MIPS liner within the helmet, air flows through the vents unobstructed. It also means there’s less material in contact with your head, which makes for a cooler, more comfortable lid. The Aether features 11 generous vents and internal channels to keep air flowing over your head.

Aether MIPS
The Aura arches add reinforcement without adding a lot of weight. Photo: Dan Cavallari |

A lot of that impressive venting can be attributed to the Aura reinforcing arches. Those clear bits in between the vents reinforce the helmet so the vents can be made larger, and they do so without adding weight or unnecessary bulk. It’s a clever solution to the venting vs. strength balance.


Roc Loc Air
Giro’s Roc Loc Air is best-in-class when it comes to fit systems. Photo: Dan Cavallari | 

Throughout all of my helmet testing, no fit system has yet unseated Giro’s Roc Loc Air system as the most comfortable, easiest to use, and least obtrusive. It rarely, if ever, interferes with my sunglasses, there are no pinch points, and it adjusts in minute increments so you can dial in your fit quickly and easily. The clicks are positive and the dial is easy to grab with two fingers. It just works.

Riding the Aether

helmet side
Sleek styling makes this one attractive helmet. Photo: Dan Cavallari |

I’ve had this helmet for a couple of years now and throughout all my other helmet testing, I always come back to the Aether because it’s well-vented, light, and stylish. Most of my riding is on pavement — long, hot, flat stretches for miles before I reach the big climbs near Golden, Colorado — with occasional forays onto gravel.

The Aether never moves once I’ve got it cinched where I want it. It doesn’t pinch uncomfortably, and it creates a sort of hugging feel around my head. Even as the padding has worn in over time, the Aether feels plenty cushioned against my head, especially against my forehead where I would expect to feel pressure as the padding packs in.

And for a helmet that touts MIPS capabilities, the Aether breathes exceptionally well since it doesn’t actually have a more traditional MIPS liner. That means there’s far less material directly in contact with the rider’s head, so breathability abounds. Even at slow speeds, you get plenty of airflow to keep you cool.

The rubber pads on the front of the helmet also provide an ideal place to stow your eyewear when you’re not wearing it. This came in handy as dusk set in on several rides; the glasses stay put, thanks to the tackiness of the pads, so you don’t have to worry about them falling off when you look down.

Aether verdict

Simply stated, the Aether is currently the best road helmet on the market right now. It takes a novel approach to rotational forces, which helps maintain the helmet’s other abilities — venting in particular. The Roc Loc Air fit system remains the most solid and unobtrusive of all the fit systems I’ve tested.

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