Giro's ethereal new Prolight helmet is roughly 60-120g lighter than most top-end lids with an actual weight of just 181g for our medium-sized CPSC-certified sample (Euro versions are even lighter). While that may not sound like much on paper, it's a very noticeable difference after a few hours on the road and Giro makes few sacrifices in getting there, too.
To help save weight, the Prolight does without an internal reinforcement skeleton so the vents are necessarily downsized to maintain structural integrity. Ventilation is far better than expected nonetheless though thanks to extra-deep interior channeling that makes the most of whatever air is coming in by funneling it straight over the top of your head.
Total airflow admittedly feels a half step behind Giro's Ionos and Atmos models (and some top pros notably reverted back to the Ionos during the helmet's introduction at this year's Tour de France) but to be fair, that still puts the Prolight on par with – or even better than – flagship models from some other brands we've tried.
General comfort is beyond reproach, though. The pared-down Roc Loc SL retention system is shockingly minimal with just a pair of spindly supports on the sides and an elastic band joining the straps at the rear but the end result is remarkably effective as it both holds the helmet on securely and practically disappears on your head. If anything, the softer materials are even more comfortable than usual for those with close-cropped hair, too.
While there's no conventional ratchet or dial out back, Giro does at least include a three-position anchor up front to help tweak the circumference if needed. Save for the tightness around the chin, the lightweight webbing is wholly fixed but Giro has obviously done its homework here as we never felt the need to adjust the fore-aft position during testing. If strap fit around the ears has caused you issues in the past, it'll be best to try one on beforehand to make sure the fixed position will work.
The aesthetics are unfortunately a bit more polarizing. Some folks we polled liked the look but most others said the smaller vents aren't what they're used to seeing on a high-end helmet and somehow the red, white and black graphics scheme on our particular tester doesn't quite look the part, either. Thankfully Giro will offer the Prolight in four color options so one might suit you better than the others.
Comfortable? Yes. Airy? Surprisingly so. Light? Undoubtedly. Good looking? Best for you to decide for yourself.