Leatt All Mountain 4.0 Helmet - S - Brushed
The AllMtn 4.0 helmet delivers DH-certified protection in a lightweight, open-face design—giving aggressive trail and e-MTB riders downhill-level impact protection. Built with in-moulded EPS + EPO impact foam for enhanced energy absorption, it is certified to ASTM F1952-15 (downhill MTB) and NTA 8776 (e-bikes going up to 45km/h / 28 mph) standards—making it an ideal choice for aggressive rides and e-MTB adventures. Leatt's 360° Turbine Technology helps reduce rotational forces and absorb low-speed impact energy, while the impact foam provides high-speed impact protection—working together as a 3-in-1 safety system. The modern profile meets the highest safety standards, yet it remains lightweight and breathable, with a moisture-wicking liner to manage sweat. A Fidlock magnetic buckle makes for easy one-handed closure, and the adjustable breakaway visor adds another layer of protection in a crash. With a secure fit system, integrated eyewear dock, and sleek design, the AllMtn 4.0 is built for riders pushing the limits.
Features
- Shell: Lightweight polymer shell
- 3-in-1 safety system: When combined with the impact foam, 360° Turbine Technology offers a unique 3-in-1 safety system by protecting against low-speed impacts, high-speed impacts, and rotational forces
- Impact foam: In-moulded EPS + EPO impact foam for superior energy absorption
- Turbines: 360° Turbine Technology • Rotation protection: The optimally designed turbine discs enable the helmet to move slightly on the head upon impact, helping to reduce peak acceleration to the head & brain • Low impact protection: The special energy absorbing material in the turbines absorbs low impact energy associated with concussion
- Ventilation: 18 vents effective even at low speeds
- Liner: Moisture wicking, breathable, anti-odour and washable inner liner
- Fit system: Flat Lock Strap divider and fit system developed for custom fit, ease, and comfort
- Closure: Fidlock magnetic closure system
- Visor: Adjustable visor with breakaway function for rotational impact force reduction
- Other features: Sunglasses dock port for easy, secure storage • Soft touch and moisture wicking chin straps • Plastic-free packaging
- Weight: From 430g (0.95 lbs)
- Certifications: AS/NZS 2063:2008, EN1078, CPSC 1203, ASTM F1952-15, NTA 8776 (Helmets for S-EPAC riders)
- Crash replacement: 3-year Leatt Helmet Replacement Programme
- Sizes: S: 51–55 cm (20–21 5/8 in) M: 55–59 cm (21 5/8–23 ¼ in) L: 59–63 cm (23 ¼–24 ¾ in)
Product Information
Product Information
Shipping & Returns
Shipping & Returns




Leatt All Mountain 4.0 Helmet - S - Brushed
Leatt All Mountain 4.0 Helmet - S - Brushed
The AllMtn 4.0 helmet delivers DH-certified protection in a lightweight, open-face design—giving aggressive trail and e-MTB riders downhill-level impact protection. Built with in-moulded EPS + EPO impact foam for enhanced energy absorption, it is certified to ASTM F1952-15 (downhill MTB) and NTA 8776 (e-bikes going up to 45km/h / 28 mph) standards—making it an ideal choice for aggressive rides and e-MTB adventures. Leatt's 360° Turbine Technology helps reduce rotational forces and absorb low-speed impact energy, while the impact foam provides high-speed impact protection—working together as a 3-in-1 safety system. The modern profile meets the highest safety standards, yet it remains lightweight and breathable, with a moisture-wicking liner to manage sweat. A Fidlock magnetic buckle makes for easy one-handed closure, and the adjustable breakaway visor adds another layer of protection in a crash. With a secure fit system, integrated eyewear dock, and sleek design, the AllMtn 4.0 is built for riders pushing the limits.
Features
- Shell: Lightweight polymer shell
- 3-in-1 safety system: When combined with the impact foam, 360° Turbine Technology offers a unique 3-in-1 safety system by protecting against low-speed impacts, high-speed impacts, and rotational forces
- Impact foam: In-moulded EPS + EPO impact foam for superior energy absorption
- Turbines: 360° Turbine Technology • Rotation protection: The optimally designed turbine discs enable the helmet to move slightly on the head upon impact, helping to reduce peak acceleration to the head & brain • Low impact protection: The special energy absorbing material in the turbines absorbs low impact energy associated with concussion
- Ventilation: 18 vents effective even at low speeds
- Liner: Moisture wicking, breathable, anti-odour and washable inner liner
- Fit system: Flat Lock Strap divider and fit system developed for custom fit, ease, and comfort
- Closure: Fidlock magnetic closure system
- Visor: Adjustable visor with breakaway function for rotational impact force reduction
- Other features: Sunglasses dock port for easy, secure storage • Soft touch and moisture wicking chin straps • Plastic-free packaging
- Weight: From 430g (0.95 lbs)
- Certifications: AS/NZS 2063:2008, EN1078, CPSC 1203, ASTM F1952-15, NTA 8776 (Helmets for S-EPAC riders)
- Crash replacement: 3-year Leatt Helmet Replacement Programme
- Sizes: S: 51–55 cm (20–21 5/8 in) M: 55–59 cm (21 5/8–23 ¼ in) L: 59–63 cm (23 ¼–24 ¾ in)
Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
The AllMtn 4.0 helmet delivers DH-certified protection in a lightweight, open-face design—giving aggressive trail and e-MTB riders downhill-level impact protection. Built with in-moulded EPS + EPO impact foam for enhanced energy absorption, it is certified to ASTM F1952-15 (downhill MTB) and NTA 8776 (e-bikes going up to 45km/h / 28 mph) standards—making it an ideal choice for aggressive rides and e-MTB adventures. Leatt's 360° Turbine Technology helps reduce rotational forces and absorb low-speed impact energy, while the impact foam provides high-speed impact protection—working together as a 3-in-1 safety system. The modern profile meets the highest safety standards, yet it remains lightweight and breathable, with a moisture-wicking liner to manage sweat. A Fidlock magnetic buckle makes for easy one-handed closure, and the adjustable breakaway visor adds another layer of protection in a crash. With a secure fit system, integrated eyewear dock, and sleek design, the AllMtn 4.0 is built for riders pushing the limits.
Features
- Shell: Lightweight polymer shell
- 3-in-1 safety system: When combined with the impact foam, 360° Turbine Technology offers a unique 3-in-1 safety system by protecting against low-speed impacts, high-speed impacts, and rotational forces
- Impact foam: In-moulded EPS + EPO impact foam for superior energy absorption
- Turbines: 360° Turbine Technology • Rotation protection: The optimally designed turbine discs enable the helmet to move slightly on the head upon impact, helping to reduce peak acceleration to the head & brain • Low impact protection: The special energy absorbing material in the turbines absorbs low impact energy associated with concussion
- Ventilation: 18 vents effective even at low speeds
- Liner: Moisture wicking, breathable, anti-odour and washable inner liner
- Fit system: Flat Lock Strap divider and fit system developed for custom fit, ease, and comfort
- Closure: Fidlock magnetic closure system
- Visor: Adjustable visor with breakaway function for rotational impact force reduction
- Other features: Sunglasses dock port for easy, secure storage • Soft touch and moisture wicking chin straps • Plastic-free packaging
- Weight: From 430g (0.95 lbs)
- Certifications: AS/NZS 2063:2008, EN1078, CPSC 1203, ASTM F1952-15, NTA 8776 (Helmets for S-EPAC riders)
- Crash replacement: 3-year Leatt Helmet Replacement Programme
- Sizes: S: 51–55 cm (20–21 5/8 in) M: 55–59 cm (21 5/8–23 ¼ in) L: 59–63 cm (23 ¼–24 ¾ in)


















