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  • While most helmets protect only against direct impact, MIPS technology reduces rotational forces when the helmet gets hit at an angle
  • In-mold technology bonds the helmet's tough outer microshell to the impact-absorbing liner, creating a light, strong helmet
  • Roc-Loc® 5 suspension fit system is easy to adjust with one hand
  • 25 vents allow cooling airflow


View all Giro Road Bike Helmets

REI membership


Best Use Road Cycling
Helmet Style Road
Helmet Construction In-mold
Shell Material Polycarbonate
Head Circumference
20 - 21.75 inches
21.75 - 23.25 inches
Vents 25
Visor No
Weight Unavailable
Gender Women's
Construction In-Mold
Rated 5 out of 5 by from Great Helmet! Very light, comfortable fit, love the adjustment factor in the back. My prior helmet was always sliding around, this sits in place.
Date published: 2017-06-05
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how much does this helmet weigh?

Asked by: biketreker
​The helmet weighs approximately 10 ounces.
Answered by: REIservice
Date published: 2016-07-26

To which standards is this helmet certified? Snell? ASTM? CPSC?

Asked by: MM Shaw
The Sonnet MIPS Bike Helmet is certified to CPSC standards and features MIPS, which is a leading slip-plane technology inside the helmet designed to reduce rotational forces that can result from certain impacts.
Answered by: REIservice
Date published: 2016-05-12

REI, I love you, but why is this helmet (including the excellent MIPS technology) priced at $110? I am thankful to have checked the website for your price as I was able to buy the same product, brand new, for $65 at another Seattle bike shop.

Asked by: cstar
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