From the manufacturer

The AllMtn 1.0 helmet delivers trusted Leatt protection and trail-ready features in a lightweight, great-value package. With 360° Turbine Technology to help reduce rotational forces and absorb low-speed impact energy, plus in-molded impact foam for high-speed impact protection, it offers a 3-in-1 safety system you can count on. The polymer shell includes extended rear coverage for added protection, while 14 vents keep airflow moving on climbs and descents. An adjustable fit system ensures a secure, personalized fit. For young riders letting it rip on the trails, the AllMtn 1.0 has you covered.

Features

• SHELL: Polymer Compound 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-molded impact foam for great 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: MaxiFlow impact foam air channels • 14 vents effective even at low speed
• LINER: Moisture wicking, breathable, and washable inner liner
• FIT SYSTEM: Adjustable fit system for personalized comfort and secure stability
• CLOSURE: Traditional side release buckle
• VISOR: Adjustable visor with breakaway function for rotational impact force reduction
• OTHER FEATURES: Plastic-free packaging
• CERTIFICATIONS: AS/NZS 2063:2008, EN1078, CPSC 1203

SIZES:
Jr XS: 50–54cm (19 2⁄3–21 ¼ in)