You're going to LOVE the fit. Try it on and experience our perfect fit. If you don't love it, send it back in new and unused condition within 30 days for an exchange or full refund*. Risk free.
Free US Shipping
We offer Free Shipping on all orders over $99 within the US. During select promotions & holidays we will offer Free Shipping on all orders within the US.
Easy Returns
We have a very easy 30-day Return Policy! Please submit a Customer Support Ticket to get a Return Authorization so we can process your return or exchange.
3 Year Warranty
We stand behind our products – with a 3 year warranty against materials and workmanship for all helmets.
100% Secure Checkout
At 509 we use the best SSL certificate and the most trusted payment processors provided by Shopify Payments.
Reinvented to ride even harder, the second generation of the bestselling 509 Altitude series unleashes a whole new animal. Lighter, stronger, and even more comfortable thanks to a new hand lay-up fiberglass construction, the 509 Altitude 2.0 Helmet excels in any terrain or condition. Includes the Fidlock® magnetic strap buckle for easy one-handed operation, plus customizable features like a removable Pro-Series Breathbox to get you through a full season of extremes.
Key Features
- Hand lay-up fiberglass composite construction for stronger, lighterweight, and better fit construction
- DOT/ECE certified in USA
- One piece eye port trim
- XS to 4X sizes available in three shells for optimal fit and minimal weight
- Upper vents with on/off shutter closure for airflow control
- Go-Pro® mounting capability, improved design
- Fidlock® The Fidlock System is a cutting-edge magnetic chinstrap buckle used in motorsport helmets ensuring quick, secure, closures with one hand and is DOT and ECE compliant.chinstrap strap closure for easy in and out
- Perfect fit between helmet eyeport and 509 goggles
- Pro-Series Breathbox for complete protection, removeable for great air flow
- WARNING for California Residents
Specs
- Weight: DOT/ECE 1200 grams
Size Guide
Not sure about your size? Try on at your local dealer!
*Street Helmets are a tighter fit due to cheekpad compression, however, they do pack out over time/use.
How to Measure
When measuring your head, use a cloth tape. Start it just above your eyebrows and circle it around the thickest point in the rear of your head and then reference the size guide below.
Scroll to the right to see more sizes
| Size | US Hat Size | Inches | Centimeters |
| X-Small | 6 5/8 - 6 3/4 | 20 7/8 - 21 1/8 | 53 - 54 |
| Small | 6 7/8 - 7 | 21 5/8 - 21 7/8 | 55 - 56 |
| Medium | 7 1/8 - 7 1/4 | 22 1/2 - 22 5/8 | 57 - 58 |
| Large | 7 3/8 - 7 1/2 | 23 1/4 - 23 1/2 | 59 - 60 |
| X-Large | 7 5/8 - 7 3/4 | 24 - 24 1/4 | 61 - 62 |
| 2X-Large | 8 | 24 3/4 - 25 | 63 - 64 |
| 3X-Large | 8 3/4 | 25 1/4 - 25 3/4 | 64 - 65 |
| 4X-Large | 9 | 26 - 26 1/4 | 66 - 67 |
| Youth Small | 6 | 18 1/8 - 18 7/8 | 47 - 48 |
| Youth Medium | 6 1/8 - 6 1/4 | 19 1/4 - 19 5/8 | 49 - 50 |
| Youth Large | 6 3/8 - 6 1/2 | 20 - 20 1/2 | 51 - 52 |
Pressure Points
When trying on a helmet, take note of any pressure points on your forehead—a sign that the helmet is too round. Pressure points on the sides of your head indicate a helmet is too oval for the shape of your head. After you buy a new helmet, try wearing it for 30 to 45 minutes to check for pressure points before using it on a ride.
Pressure Points
When trying on a helmet, take note of any pressure points on your forehead—a sign that the helmet is too round. Pressure points on the sides of your head indicate a helmet is too oval for the shape of your head. After you buy a new helmet, try wearing it for 30 to 45 minutes to check for pressure points before using it on a ride.
Get the Women's Range Look
