Never lose your line of sight again, thanks to our re-engineered Phantom Frame Technology. No matter how tight the trail the Sinister MX-5 Offroad Goggle will not get in the way. Boasting a 0.5″ taller field of view, perfect sloping to fit the contours of your face, and an invisible frame. You will never be distracted by the edge of your frame again. Fits perfectly inside of the 509 helmets.