Giro Aries Spherical Bike Helmet

Color: Matte White
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With a smaller form and lighter weight that deliver sensational comfort and cooling power, the Giro Aries Spherical bike helmet is a premium helmet that won't distract you from the road ahead.


  • Spherical Technology Ball-and-Socket design, powered by Mips®, helps redirect impact forces away from the brain by allowing the outer liner to rotate around the inner liner
  • It also eliminates contact with hard plastic or slip planes against the skin
  • Progressive Layering™ features a dual-density liner designed to address high- and low-speed impacts for more comprehensive energy management
  • Structural integrity is bolstered by the shatter-resistant and translucent AURA reinforcing arch that runs throughout the helmet
  • 24 Wind Tunnel vents are maximized by the AURA reinforcement arch
  • In-mold construction fuses a tough polycarbonate outer shell with the helmet's impact-absorbing foam liner
  • The fusion process allows for better ventilation systems, making in-mold helmets lighter and cooler than traditional helmets
  • Combined with the massive vents, deep internal channeling forces air to flow over the scalp, providing remarkable cooling power
  • Revolutionary Roc Loc® 5+ Air fit system adds a new dimension to helmet performance by enhancing cooling as well as fit, comfort and stability
  • Using a patented design that suspends the helmet just slightly off the top of the skull, Roc Loc 5+ Air allows cool airflow to pass directly over your head
  • Roc Loc 5+ Air enhances the performance of vents and internal channeling that exhaust heat out of the helmet
  • Fit and feel adjustments mimic the Roc Loc 5, allowing you to easily custom tune fit tension and fore-aft tilt of the helmet in seconds using a single hand
  • Plush IONIC+ antimicrobial padding and a network of intricately engineered deep internal channeling elevate comfort
  • Helmet provides full lower hardbody coverage


To find your size, position a tape measure just above your ears and about 1 in. above your eyebrows. Keep the tape level to measure the circumference around the largest part of your head and then find the corresponding size in the Technical specs info.
View all Giro Road Bike Helmets

Technical Specs

Best Use

Road Cycling

Helmet Style

Road Bike

Helmet Construction


Shell Material


Head Circumference

S: 20.1-21.7 inches

M: 21.7-23.2 inches

L: 23.2-24.8 inches






S: 9.3 ounces

M: 9.6 ounces

L: 9.9 ounces



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