Troy Lee Designs A3 Uno Half Shell Mountain Bike Helmet W/MIPS - EPP EPS Premium Lightweight - All Mountain Enduro Gravel Trail Cycling MTB

Color: White
Size: X-Small/Small
Sale price$336.90
Only 10 units left


  • TOP OF THE LINE most comfortable helmet we've made to date w 3-Way Magnajust visor, comfort liner
  • CUTTING EDGE COVERAGE Tech with MIPS, industry first EPP (high speed), EPS (low speed) coverage
  • 3 YEAR WARRANTY. Includes bag with breathable mesh paneling. FIDLOCK magnetic buckle system.
  • 16 VENTS FOR MAXIMUM AIRFLOW- the most intake and exhaust vents of any half shell helmet we've made
  • Troy Lee Designs: 40 years of racing for the World's Fastest Racers. Corona, California

Product Description

Celebrating 40 Years of Creative Horsepower - Troy Lee Designs. Born in Corona, California

So comfortable you won't ever want to take it off. The A3 mountain bike helmet is a new standard in premium mountain bike helmets with luxurious comfort, patent-pending innovations in coverage, ventilation, that will keep you cool on the longest climbs with comfort and coverage on the sketchiest of descents. Highest possible score (5-STAR) from VT helmet lab so you can feel confident in all conditions.

Comfort Liner

Xstatic liner that is also quick to dry. The liner features precision cut lines for those who want to customize the fit of the helmet.


3-piece shell layup not only adds to the technical refinement aesthetic, it allows the helmet to have more design option but also allows different parts of the EPP/EPS to be laid in for additional coverage.

Sweat Management

Carefully designed Eva Foam that is installed via adhesive backing, behind the comfort liner along the front brow, directing sweat away from the eyes and optics. Helmet ships with this installed and an additional spare included.

Adjustable Visor

Patent pending magnetic adjust visor system, allowing you to easily stow your goggles on the upswing and upon putting your goggle back on-the visor will automatically click back into position via the Magnajust system.

MIPS B Series

MIPS B-Series solution allows the TLD fit system to attach directly to the MIPS LFL vs other models where the fit system is anchored in a stationary position to the side of the helmet-this solution creates an optimal 360 degree fit and a helmet that fits perfectly

Break off screws

Composite screws are made to shear on a severe impact

Impact Liner

Patent pending coverage that combines EPP low density coverage foam for low-speed coverage / co-molded with more firm EPS layer for high-speed coverage

Fidlock Buckle

Fidlock magnetic buckle for easy on and easy off, 3D molded TLD badge on surface.

A3 What's in the Box

  • Drawstring helmet sock.
  • EVA foam is installed via adhesive backing, behind the comfort liner along the front brow, directing sweat away from the eyes and optics.
  • Xstatic liner properties that is also quick to dry.
  • Composite smart-shear screws with anodized washers.
  • 15 sticker set sheet
  • Velcro strips installed via adhesive backing applied around the inner shell, and connected via Velcro to comfort liner.

What began as a hobby of a motocross racing teenager named Troy Lee, painting helmets in his parents' garage for his friends, has grown to become recognized as the premier custom helmet paint shop in the world. Troy Lee Designs supplies motocross and mountain bike gear to the world's fastest racers.

Rider Category Mid range MTB Trail helmet Mid range MTB Trail helmet Full depth coverage MTB/Enduro Trail helmet
Weight 360g 350g 375g
Rotational System MIPS C-solution (Thermoformed PC LFL) MIPS C-solution (Thermoformed PC LFL) MIPS B32 solution integrated into retention system
Adjustable Visor Yes Yes 3 position including goggle stowage
Impact liner EPS EPS/EPP EPS/EPP Comolded
Fit system retension TLD V1 TLD V2 New TLD FIT system, Full 360, Micro ratchet adjust
Liner Quick dry material Ionic comfort liner 2 piece Ionic liner
Vents 14 14 16
Coverage Mid Mid Deep. Our most coverage half shell
Goggle Stowage No No Yes

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