Sacrifice nothing with our highest performance snowmobile helmet ever. The 509 Altitude 2.0 Pro Carbon Fiber 3K Helmet boasts every advantage for the most demanding off-trail riders. 3K carbon composite construction makes it lighter, stronger, and sleeker than anything else in the lineup. For those who run at redline, the helmet maximizes airflow with open upper and rear vents plus a 40% larger chinbar intake. It also features the MIPS Brain Protection System for the highest levels of safety.