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100% Altis Helmet AW21 - £89.99 £40.49

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100% Altis Helmet

Lightweight, breathable and packed with head-protecting features, the 100% Altis Helmet is ready for mountain biking fun. And it's all at a wallet-friendly price point too. 

If you love mixing up your mountain biking, from leisurely loops of easy trails to fast-riding and swooping sweeping singletrack through to more demanding technical trails, the Altis Helmet keeps your head covered when tyre grip and skills don't quite match your ambition. 

Safety First

In the event of a crash, the Altis has two key safety features to keep you safe. First is the Multi-Density EPS foam construction. Upon impact, this shock-absorbing material dissipates and reduces the shock to your head. Extended coverage over the rear also ensures protection, no matter which way you fall. 

Next comes the Smartshock® Rotational Protective System. This system has 11 internal elastomer bumpers designed to protect the brain from the rotational forces involved in a crash. This lets you dust yourself down and keep riding when it all goes wrong. 

Get Some Air

Most of the time we hope you'll be riding and not crashing. And when you're on the go, the Altis does a great job of maintaining a cool and comfortable fit. With 14 ventilation ports, you'll feel the benefit of turbo-charged airflow over your head. Cool air is pulled in. Damp warm air is pushed out. 

Meanwhile, inside the helmet, the quick-wicking anti-microbial liner keeps you fresh and it's washable too, so no itchy head annoyance after a fun day on the hill.

Easy Adjustment

For fuss-free adjustment and to ensure your helmet stays put in a crash, 100% use their ratchet fitment system. This system cradles your head for a secure fit and a twist of the rear dial gets the fit just right. With the Nexus push release snap-buckle, you'll find it easy to get your lid on and off too. No faff. More mountain biking time. 


  • Smartshock® Rotational Protective System (11 point)
  • High-Density EPS foam injection and moulded with polycarbonate. All sized in specific moulds
  • Massive airflow with an impressive 14 ventilation ports
  • Expanded coverage while staying lightweight
  • Multi-point adjustable visor designed for maximum vision and goggle stowage
  • Washable, moisture-wicking anti-microbial liner
  • Adjustable ratcheting fitment system
  • Nexus push release snap-buckle

Buy 100% Protection from Chain Reaction Cycles, the World's Largest Online Bike Store.

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