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Leatt MTB 4.0 AllMtn V21 Bike Helmet

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Leatt MTB 4.0 AllMtn V21 Bike Helmet

sku# 195661
Leatt - MTB 4.0 AllMtn V21 Bike Helmet
Model Info


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Product Info

The Leatt MTB 4.0 AllMtn V21 Bike Helmet leads the pack for Leatt's half-shell mountain bike helmet collection. This stalwart head protector uses two different densities of impact foam to defend against high and low speed crashes, 360 ̊ Turbine Technology to protect from rotational impacts, and 13 big vents to protect against your head turning into a hot sweaty mess. As an added bonus, the 4.0 includes a docking port for your shades and an adjustable visor that makes rooms for your goggles, so no matter your eye protection preference, it's got you covered.

Product Details


Lightweight Polymer Compound Shell

EPS + EPP Impact Foam


In-molded Construction


Dial Adjuster


Maximized Ventilation with 13 Vents

Additional Features

Sunglasses Docking Port

Fidlock Magnetic Closure System

Moisture Wicking, Breathable, and Washable Inner Liner

Adjustable Visor with Breakaway Function

360 ̊ Turbine TechnologyThe helmet is lined with 360 ̊moving discs constructed from an energy-absorbing shape and material, which reduce rotational acceleration to the head and brain, and absorb energy upon impact at concussion level. Reduces peak brain acceleration by up to 30% at impact speeds associated with concussion, and reduces peak brain rotational acceleration by up to 40%.

Safety Standards

AS/NZS 2063:2008

EN 1078

CPSC 1203


  • Material: EPP, EPS, Polymer
  • Biking Type: Mountain More 
  • Helmet Style: Half Shell
  • Helmet Venting: Fixed Venting
  • Visor: Yes
  • Removable Ear Pads: No
  • Adjustable Fit: Yes
  • MIPS: No
  • Weight (g): 850
  • Warranty: 1 Year
Size S M L
Weight (g) 850

Other Notes

Leatt products can only be shipped within the United States and Canada



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