Smith Mainline MIPS Bike Helmet

Color: White/Black
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Featuring complete Koroyd coverage and a Mips® rotational system, the Smith Mainline helmet provides exceptional protection; plus, internal air channels and open exhaust ports maximize breathability.

Location Image of color White/BlackLocation Image of color White/BlackLocation Image of color White/Black
Location Image of color White/Black


  • With 21 optimized vents, the AirEvac ventilation system allows goggles and helmet to function as a system, venting warm, moist air away from the goggles—and away from the head
  • Koroyd provides superior impact absorption, design flexibility and ventilation when compared to materials traditionally used in helmet construction
  • Utilizing crumple-zone cylinders that crush uniformly on impact, Koroyd manages energy more efficiently with less volume than traditional protection materials
  • Rotational motion can cause brain injuries; with Mips, a low-friction layer slides 10 to 15 mm in all directions, reducing rotational motion to the brain during impact
  • Unique pad kit includes 3 sets of sized cheekpads, 2 sets of sized crown liners and 2 neck rolls to ensure a proper fit̵all of which can easily be removed for cleaning
  • Pads are made from Hybrid X-Static/XT2 for antibacterial performance
  • Ride with confidence, knowing the Mainline is secured with a tried-and-true D-ring chin strap fastener
  • Lightweight Aerocore in-mold construction
  • Adjustable visor
  • Camera- and light-mount compatible
  • Downhill certification: ASTM F1952
  • Certification: CPSC, CE EN 1078
  • E-Bike helmet certification: NTA-8776


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 Smith Mountain Bike Helmets

Technical Specs

Best Use

Mountain Biking

Helmet Style


Helmet Construction


Shell Material


Head Circumference

S: 20.1-21.7 inches

M: 21.7-23.2 inches

L: 23.2-24.4 inches






1 lb. 11 oz.



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