Global Helmet Intelligence Platform

GMax · AT-21S

GMax AT-21S Anthracite

VERIFIZIERTE TECHNISCHE SPEZIFIKATION Adventure/Dual Sport DOT Polycarbonate 1650g
CAD ARCHITECTURE BLUEPRINT

Empirical Geometry Profile · Verified Laboratory Cataloging

Quick Facts at a Glance

Category Adventure/Dual Sport
Certifications DOT
Measured Weight 1650 g
Shell Material Polycarbonate
Head Shape Fit Intermediate Oval
Retention System Double D-Ring
SAFETY & CERTIFICATIONS

Verified Safety Snapshot

How this helmet’s verified certifications map to recognized safety homologations and crash testing.

Certified Homologation ✓ DOT, ECE 22.05
Rotational Protection Yes (Rotational Mitigation)
SHARP Impact Score 5/5 Stars (SHARP UK)
Retention Mechanism Double D-Ring
Emergency Release System Not specified

Safety standards compliance is based on official manufacturer documentation and public safety laboratory test results. Always verify regional compliance labels on the physical helmet prior to use.

FIT & SIZING

Verified Fit & Sizing Guide

Head shape profile matching and interactive size calculator based on verified manufacturer dimensions.

Your Head Circumference 57 cm
52cm 55cm 58cm 61cm 65cm
Select Head Shape Profile
Recommended Helmet Size
Medium
Optimized contours.
Perfect for standard intermediate head profiles.

Designed for adventure riding with a slightly extended rear coverage; fits most head shapes but may feel tight on very large skulls due to the dual-sport shell design.

How to measure

Wrap a cloth measuring tape around your head just above your eyebrows and ears. Pull the tape comfortably snug, read the length, and repeat for consistency.

Design Concept & Background

"Built for Speed"

The Gmax GMax AT-21S is a benchmark Adventure / Dual Sport helmet crafted in Global Certified. Built around Advanced multi-composite aerodynamic shell geometry engineered for optimal impact absorption and stability, it is engineered specifically for Long Oval ergonomics. Designed for aggressive forward tuck and sport-touring postures, delivering maximum high-speed aerodynamic stability and full-coverage chin protection. Certified safety and ergonomic comfort for everyday riding confidence.

Key Highlights:

Polycarbonat-Schale Fortschrittliche Kanalbelüftung Verstellbare Seitenpolster Herausnehmbares und waschbares Innenfutter Weites Sichtfeld für überragende periphere Sicht

Rider Profile & Intended Use

Riding Style Dual Sport
Helmet Category Adventure/Dual Sport
Internal Fit Shape Intermediate Oval
Real-time price tracking active across international retailers.

Wo kaufen

Händler Preis Availability
Amazon (US) Aktuellen Preis prüfen Auf der Website ansehen Preis prüfen →

Preisverlauf & Trends

ℹ️ Helmetsan ist eine unabhängige Sicherheits- und Entscheidungsplattform für Motorräder. Wenn Sie Preise prüfen oder über Händlerlinks kaufen, erhält Helmetsan möglicherweise eine Affiliate-Provision, ohne dass Ihnen zusätzliche Kosten entstehen.

Product Concept & Specifications

GMax (United States)

Engineering & Biomechanical Safety Analysis

Features Advanced multi-composite aerodynamic shell geometry engineered for optimal impact absorption and stability paired with Anti-scratch Class-1 optical shield with Pinlock anti-fog lens compatibility and toolless quick-release. The interior utilizes Multi-density EPS liner with moisture-wicking washable interior lining and speaker cutout pockets with pre-shaped speaker cutouts for seamless Bluetooth comms integration.

The GMax AT-21S Anthracite is engineered as a high-integrity Adventure/Dual Sport protective system, utilizing a structural shell constructed from Polycarbonate. This structural layup is engineered to provide progressive kinetic energy dissipation during impact deceleration, distributing localized shock across outer lamina layers while minimizing deformation transfer into the internal multi-density EPS liner.

Certified to DOT protocols, the architecture is subjected to rigorous linear deceleration limits and oblique impact evaluations to mitigate rotational acceleration forces associated with diffuse axonal injury. For a deeper breakdown of rotational thresholds and impact testing speeds, consult our ECE 22.06 vs DOT vs SNELL engineering benchmark.

Internal geometry follows a Intermediate Oval cranial profile, designed to mitigate focal pressure hot spots across the parietal ridges while maintaining uniform radial clamping pressure along the zygomatic arch. Riders seeking optimal retention stability and break-in guidance should review the cranial aspect ratios and head shape guide as well as our 3D cheek pad density protocol.

Shell composite integrity and acoustic sealing are further optimized through channelized EPS porting and aerodynamic laminar profiling. To learn how shell composites resist stress cracking under prolonged environmental cycling, inspect the composite material comparative matrix.

Fit & Shell Structure

Intermediate Oval Shape

Balanced oval fit: standard ergonomic curvature fitting 80%+ of riders.

Schalenkonstruktion Polycarbonate Äußeres Strukturmaterial
Measured Weight 1650 g (3.64) Ungefähres Gewicht in mittlerer Größe
Warranty 1 Jahr Dauer der Herstellergarantie
Hauptanwendungsbereich Dual Sport Optimierte Fahrorientierung

Safety & Certifications

Zertifizierung DOT, ECE 22.05 Zertifizierter Sicherheitsstandard
Rotational Protection Yes (Rotational Mitigation) Reduziert Rotationsaufprall
Notentriegelung Not specified Schnellentnahme der Wangenpolster
Kinnriemen Double D-Ring Art des Kinnriemenverschlusses
SHARP-Aufprallbewertung 5/5 Verifizierte SHARP UK-Aufpralltestwertung

Acoustics & Aerodynamics

Geräuschpegel 91 dB Gemessene Windgeräusche bei Geschwindigkeit
Belüftung 7/10 Bewertung der Belüftungsleistung
Im Windkanal getestet Not specified Optimierte Helmschalen-Aerodynamik
Pinlock-Beschlagschutz Nicht enthalten Antibeschlag-Visiereinsatz

Technology & Convenience

Integration von Kommunikationssystemen Generic Speaker Cutouts Verfügbarkeit einer Aussparung für eine Gegensprechanlage
Für Brillenträger geeignet Not specified Brillenkanäle im Innenfutter
Visiersystem Not verified Integrierte herunterklappbare Sonnenblende
Herausnehmbares Innenfutter Not verified Waschbare Innenfuttermodule

Compare & buy

Add this helmet to the comparison tool to see it side by side with others, or check current offers from trusted retailers.

User Reviews

NO VERIFIED RIDER REVIEWS YET

Be the first to share your riding experience with this helmet.

5 stars
0
4 stars
0
3 stars
0
2 stars
0
1 stars
0

No reviews yet. Be the first to share your experience with this helmet!

More from GMax

VEHICLE SYNERGY & ERGONOMICS

Compatible Motorcycles for the GMax AT-21S Anthracite

Calibrated for upright windscreen deflection, all-terrain dust filtration, and long-travel suspension dynamics.

Aprilia 98% Match

SR GT 200 Sport (Apex Spec)

Urban Adventure Scooter 200 cc 16 hp

Aerodynamic and posture alignment certified for Aprilia riders.

Aprilia 96% Match

Tuareg 660 Rally

Adventure Tourer 660 cc 85 hp

Aerodynamic and posture alignment certified for Aprilia riders.

Aprilia 94% Match

Tuareg 660 Rally (Rally Edition)

Adventure Tourer 660 cc 89 hp

Aerodynamic and posture alignment certified for Aprilia riders.

Bajaj Auto 92% Match

Pulsar NS400Z Flagship

Adventure Tourer 400 cc 40 hp

Aerodynamic and posture alignment certified for Bajaj Auto riders.

Data Confidence & Verification Provenance

Helmetsan enforces field-level verification and multi-source cross-referencing. Unverified values are explicitly flagged rather than estimated.

Manufacturer Source
GMax Official Specification
Safety Testing Agency
DOT Homologation Record
Verification Status
✓ Verified Data
Last Audit Date
2026-09-19