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Smith Optics Mainline MIPS Mountain Bike Helmet

Smith Optics Mainline MIPS Mountain Bike Helmet
  • Color: Matte Black
  • Color: Matte Black
  • Color: Matte Black
  • Color: Matte Black
  • Color: White/Black
  • Color: White/Black
  • Color: White/Black
  • Color: Matte Archive Wild Child
  • Color: Matte Archive Wild Child
  • Color: Matte Archive Wild Child
  • Color: Matte Coyote/Indigo
  • Color: Matte Coyote/Indigo
  • Color: Matte Coyote/Indigo
Color: Matte Black
Size: Select size
Please select options Unavailable


Give credit where credit's due. Thank your mom, your legs, and your gear for giving you the opportunity to land that rocky gap.

Made for going big, going fast, or both, the Smith Mainline is our pinnacle, downhill certified enduro bike helmet.

Safety innovations like Koroyd and MIPS provide energy-absorbing impact protection so you have the confidence to get aggressive on the trail. It doesn't matter if you're slaying the EWS in Whistler or suffering through the last stage of your local enduro race, you need a breathable, lightweight helmet that pairs well with goggles and fits like a glove.

The Mainline integrates with your bike goggles for efficient venting and fog-free vision. Multiple pad sets including liners and neck-rolls let you customize the fit.

  • 21 fixed vents for consistent airflow

  • Adjustable visor

  • Hybrid X-STATIC® / Ionic+® anti-bacterial performance lining for odor resistance

  • Designed for ultimate integration with Smith performance goggles for maximum comfort, venting and storage convenience

  • AirEvac ventilation system integrates with Smith goggles for fog-free lenses

  • Three washable cheek pad kits, two crown liners and two neck rolls let you fine-tune the fit

  • D-ring chin strap fastener for a snug fit

Mips® Brain Protection System reduces rotational forces caused by angled impacts to the head.

KOROYD ultimate protection absorbs more energy and works better than traditional materials because it creates crumple zones by using core tubular technology. This outperforms other materials at every stage of compression, helping reduce the risk of injury.

Read more about Koroyd at

Small 51 - 55 cm
Medium 55 - 59 cm
Large 59 - 62 cm
X-Large 61 - 65 cm

How To Fit Your Smith Helmet


Weight (g) 770g (Size Medium)
Retention System D-ring Chin Strap
Protection MIPS (Multi-Directional Impact Protection System) | Complete KOROYD® coverage
Certification CPSC CE EN 1078 | ASTM F1952 downhill | NTA-8776 E-Bike certified
Type Mountain Downhill

* Subject to change without notice.

Part Numbers

Option UPC MPN Store SKU
Matte Black / Small 716736216850 E007429RX5155 HEL542792402
Matte Black / Medium 716736216867 E007429RX5559 HEL548653182
Matte Black / Large 716736216874 E007429RX5962 HEL544108762
White/Black / Small 716736336503 E007423OD5155 HEL542561004
White/Black / Medium 716736336510 E007423OD5559 HEL549010434
Matte Archive Wild Child / Medium 716736924533 E007421NZ5559 HEL658985534
Matte Archive Wild Child / Large 716736924540 E007421NZ5962 HEL659193314
Matte Coyote/Indigo / Medium 716736924564 E007421O65559 HEL616753414