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SKU:
F01009900-140-204
Altitude 2.0 Carbon Fiber 3K Hi-Flow Helmet
$301.95
$399.95
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3 Year Warranty
We stand behind our products – with a 3 year warranty against materials and workmanship for all helmets.
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Reinvented to ride even harder, the second generation of the bestselling 509 Altitude series unleashes a whole new animal. For those who run at redline, the new 509 Altitude 2.0 Carbon Fiber 3K Hi-Flow Helmet maximizes airflow with open upper and rear vents plus a 40% larger chinbar intake. Everything else is what you’d expect from one of the world’s bestsellers, including a new hand lay-up carbon composite construction that makes this helmet lighter, stronger, and even more comfortable.
Key Features
- Hand lay-up carbon fiber 3K Carbon Fiber 3K is a specific type of carbon fiber used in the hand lay-up process where the carbon fiber's weave pattern consists of 3,000 individual carbon fibers per tow, resulting in an intricately woven and tightly packed light weight structure.composite construction
- XS to 4X sizes available in three shells for optimal fit and minimal weight
- Upper vents for airflow control (shutter closure not available on Storm Chaser and Cyan Navy colors)
- 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, removable for optimal air flow
- Hi-Flow venting technology allowing more airflow through a 40% larger chinbar intake.
- 509 helmet bag included
- WARNING for California Residents
Specs
- Weight: ECE 1050 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.
