509 Altitude 2.0 Snowmobile Helmet - Lightweight, Strong Protection

In this review of the 509 Altitude 2.0 Snowmobile Helmet the bottom line is simple: riders who want a lighter, well-fitting DOT certified off-road helmet that pairs perfectly with snow goggles will appreciate the balance of comfort and protection. Built from a hand lay-up fiberglass composite, the Altitude 2.0 aims to offer stronger, lighterweight performance and a better fit than many stock shells, and the review finds those claimed strengths translate to real-world riding comfort and control in varied winter conditions.

Key Features

• Hand lay-up fiberglass: The composite construction delivers a lighter shell that still feels solid and provides certified impact protection for snowmobiling.
• Upper vents with shutter: Adjustable on/off upper vents let riders tune airflow quickly for changing temperatures and exertion levels.
• Fidlock chinstrap closure: The magnetic chinstrap system provides fast, secure closure and makes getting the helmet on and off easier when wearing gloves.
• Pro-Series Breathbox: The removable breathbox enhances breath management and can be taken out to open airflow for higher-output riding or colder conditions.
• DOT certified: Meeting FMVSS 218 means the helmet satisfies US safety standards for on-road and powersports use, offering tested protection.

Who It's For

The Altitude 2.0 is best for snowmobile riders and off-road powersports enthusiasts who value a lightweight, well-fitting helmet that integrates with goggles and offers adjustable ventilation. Riders who prioritize comfort on long runs and need a helmet that manages breath and airflow will likely be satisfied.

Less suitable are riders who require full-face motorcycle helmets designed primarily for high-speed street use with integrated communication systems; this model focuses on snowmobile and off-road fit, ventilation, and goggle compatibility rather than street touring features.

Pros & Cons

Pros

• Lightweight fiberglass construction gives a solid feel without excess weight.
• Adjustable upper vent shutters and removable breathbox provide flexible airflow control.
• Fidlock chinstrap makes securing the helmet quicker and more glove-friendly.
• DOT approval ensures it meets FMVSS 218 safety standards for certified protection.

Cons

• Not optimized for street touring features like integrated comms; focused on snowmobile/off-road use.

Specifications

Brand	509
Shell material	Hand lay-up fiberglass composite
Inner features	Pro-Series Breathbox, removable
Ventilation	Upper vents with on/off shutter closure
Closure	Fidlock chinstrap
Certification	DOT approved; meets FMVSS 218

Our Verdict

The 509 Altitude 2.0 is a solid choice for riders who want a lighter, better-fitting snowmobile helmet that still meets DOT safety standards; its ventilation controls, removable breathbox, and glove-friendly Fidlock make it a practical, good-value option for off-road and snow conditions.

Frequently Asked Questions

Is this helmet DOT certified?
Yes, the Altitude 2.0 is DOT approved and meets the FMVSS 218 standard.

Can the breathbox be removed for more airflow?
Yes, the Pro-Series Breathbox is removable to increase ventilation when needed.

How does the chinstrap close with gloves on?
The Fidlock magnetic chinstrap closure is designed for quick, secure operation even while wearing gloves.