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Item # LZR000Y

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Item # LZR000Y

You depend on it.

Lazer makes its lightweight O2 Helmet for sleek, uncomplicated protection that won't slow you down on your daily rides and weekend races. Like us, Lazer understands that while you probably shouldn't ride without it, a helmet can sometimes feel bulky or suffocating enough that you'd like to — especially during hot summer rides. For the minimalists at heart, the O2 offers 24 ventilating channels, ensuring you get airflow to every part of your head even on the stickiest, slowest climbs. Protection comes courtesy of the helmet's four-piece, In-Mold, polycarbonate shell, and you can adjust the fit using Lazer's efficient Rollsys retention system. Just move a dial along the top of the helmet to ensure it stays securely in place without feeling uncomfortably tight. The O2 is finished with reflective accents to help enhance your visibility to other road users at any time of day.

Tech Specs

Shell Material:
In-Mold polycarbonate
24 vents
Fit Adjustment:
Rollsys retention system
Claimed Weight:
267 g
Recommended Use:
Manufacturer Warranty:
2 years

Size chart


Head Circumference 20.5 - 22in
(52 - 56cm)
21.7 - 23.2in
(55 - 59cm)
22.8 - 24in
(58 - 61cm)
24 - 25.2in
(61 - 64cm)
How to Measure:
Measure around your head where your hat would fit comfortably.

Reviews & Community


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Avg. ride time: 2h 35m per week
  • Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.

Put it through the wringer

  • Familiarity: I've put it through the wringer
  • Fit: True to size

I love the fit of this helmet. Of all the helmets that I tried, so far this one is the best. I think it also saved my life through a bad DH crash. The back of the helmet was cracked but my head was intact with only a concussion and dizziness for a few days. I would love to try the Z1 MIPS version (waiting for the price to drop a little).

Put it through the wringer
Avg. ride time: 2h 52m per week
  • Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.

Saved my head, and looked great doing it

    I didn't have super high expectations when I bought this helmet. After all, it's literally half the cost of most of the really good helmets out there (Octal, Synthe, and even Lazer's own Z1.) I was thrilled with the way this helmet fit and looked. I can't really imagine a helmet being a whole lot better than this, and especially not at twice the price. I only had the opportunity to race with this helmet once, at a very hot XC race in southern Utah, and it did amazingly well. Unfortunately my helmet met an untimely end when I went over the bars. The O2 did an excellent job of preventing my brains from being splattered all over the trail.